TYPE SPECIES

Pionosyllis fusigera Augener, Reference Augener1913, by present designation.

DIAGNOSIS

Body slender, small, of medium to meiofaunal size. Without ciliary bands. Segments fused on one species. Prostomium provided with four eyes, three antennae and two palps. Median antenna inserted on anterior margin of prostomium. Palps fused at their bases, triangular. Nuchal organs as two ciliated grooves. Two pairs of tentacular cirri. Antennae, tentacular cirri and dorsal cirri similar in shape, smooth, club-shaped, slender at base and wider distally; some dorsal cirri inflated. Subcirral papilla absent. Compound chaetae heterogomph, provided with falcigerous bidentate blades, with both teeth similar in size or slightly different; spines on margin short. Acicula tips acuminate or tricuspidate. Parapodia with prechaetal lobes short, small. Pharynx and proventricle of similar size, short. Pharyngeal tooth located in mid-pharynx. Reproduction unknown.

APOMORPHIES

Clade supported by one autapomorphy; the dorsal cirri are inflated in some segments (character 18, state 1). Another apomorphy is the presence of pre-chaetal lobes (character 28, state 1). This state of the latter character is shared with the following taxa: Ophiodromus flexuosus, Pisione longispinulata, Amblyosyllis sp., Pionosyllis marquesensis, Pionosyllis procera and genus Pionosyllis. The presence of a pharyngeal tooth in the posterior part of the pharynx (character 34, state 2) might also be an apomorphy, but it is uncertain in Pionosyllis sp. A; this character state is shared with Salvatoria kerguelensis, Prosphaerosyllis longipapillata, and the clade in the consensus tree including Opisthodonta hanneloreae and Pionosyllis sp. B.

ETYMOLOGY

From the Greek basidios meaning club, in reference to the club-shaped dorsal cirri and antennae.

KEY TO SPECIES

1. 1. Long, inflated dorsal cirri distally button-shapedBasidiosyllis fusigera.

   • Long, inflated dorsal cirri distally rounded, without a button2

2. 2. Acicula tip tricuspidate. Proximal tooth of blades of compound chaetae somewhat longer than distal tooth. Colour pattern transverse black bands. Segments of midbody fused, forming groups of 2–3 segments Basidiosyllis victoriae, sp. nov.

   • Acicula tip acuminate. Both teeth of blades of compound chaetae similar in size. Red to orange spots on dorsum. Segments not fusedBasidiosyllis kalimna

Pionosyllis fusigera Augener, Reference Augener1913: 227, pl. 3, figure 34 and text, figure 32a–c.

Basidiosyllis fusigera San Martín & Hutchings, Reference San Martín and Hutchings2006: 330, figure 60A–I.

MATERIAL EXAMINED

Western Australia, Sharks Bay, Surf Point, Outer Bar, 1–3.5 m, 16/6/1905 (ZMH V-7951, 1 syntype).

TYPE LOCALITY

Sharks Bay, Western Australia.

DISTRIBUTION

Western Australia.

HABITAT

1–3.5 m depth.

Pionosyllis kalimna San Martin & Hutchings, 2006:335, figure 65A–K.

TYPE LOCALITY

Bundegi Reef, Western Australia.

DISTRIBUTION

Only known from type locality.

HABITAT

Rocky rubble, sediment and brown algae with epiphytes, 2 m depth.

MATERIAL EXAMINED

Six Men's Bay, Barbados (west coast), on Montastrea annularis, 10 m depth, María Victoria Díaz coll., 22 May 1990, holotype (MNCNM 16.01/6062).

DESCRIPTION

Pre-epitoke specimen, with well developed notopodia from chaetiger 14, long, with notoaciculae, without natatory chaetae. Body short, slender, 2.3 mm long, 0.3 mm wide, for 32 chaetigers. Dorsum with a transverse, irregular black band across each segment beginning on chaetiger 9 (Figure 4A); bands more marked from chaetiger 11 (Figure 4C,D); posterior part of prostomium with curved dorsal band of dark pigment (Figure 4A), and ventral part with slight black pigmentation. Intersegmental furrows well defined onwards chaetiger 10; from chaetiger 11, only one intersegmental furrow visible every two or three chaetigers (Figure 4C,D). Prostomium ovate, wider than long, with rounded corners; four large lensed eyes in open trapezoidal arrangement, anterior pair larger. Palps short, ventrally folded, fused at bases, with dorsal furrow; antennae thick, elongate, club-shaped, slender basally and wide distally, originating on anterior margin of prostomium, median antenna shorter and thinner than lateral antennae (left antenna detaching). Peristomium dorsally reduced, covered by prostomium; dorsal tentacular cirri similar to lateral antennae, ventral tentacular cirri about 1/3 of length of dorsal tentacular cirri (both only present on right side) (Figure 4A). Dorsal cirri missing in many parapodia; alternating long, slightly shorter than body width, club shaped cirri, and shorter, less so inflated dorsal cirri (Figure 4C). Ventral cirri short, ovate. Parapodia slender, elongate, with dorsal, anterior short papilla (Figure 4B). Compound chaetae hemigomph; shafts smooth on distal part near hinge; blades bidentate, with proximal tooth longer than distal tooth; blades quite short, with straight spines on margin (Figure 4E,H,K). Anterior parapodia each with 8–15 compound chaetae (Figure 4E), diminishing to about seven in posterior chaetigers; blades of anterior chaetigers 21 µm long dorsally, 10 µm ventrally, blades of midbody parapodia 22 µm dorsally, 13 µm ventrally (Figure 4H), and blades of posterior chaetigers 16 µm dorsally, 10 µm ventrally (Figure 4K). Solitary dorsal simple chaetae (Figure 4G,J) from chaetiger 14, bidentate, with proximal tooth more prominent than distal one, provided with short, straight subdistal spines on margin. Solitary ventral simple chaetae (Figure 4L) on far posterior chaetigers, bidentate, both teeth similar, with short spines on margin. Anterior parapodia each with two aciculae (Figure 4F), only one from chaetiger 13, with tricuspidate tip (Figure 4I). Pharynx apparently short, everted and ventrally folded, pharyngeal tooth not seen. Proventricle extending through 9 segments, barrel shaped, with about 23 muscle cell rows.

Fig. 4.

Basidiosyllis victoriae, sp. nov. (A) Anterior end, dorsal view; (B) midbody parapodium, dorsal view (chaetae not drawn); (C) segments 11–12, 13–14, and 15–17, dorsal view (chaetae not drawn); (D) chaetigers 18–20 and 21–23, lateral view (chaetae not drawn); (E) compound chaetae, anterior parapodium; (F) aciculae, anterior parapodium; (G) dorsal simple chaeta, midbody parapodium; (H) compound chaetae, midbody parapodium; (I) acicula, posterior parapodium; (J) dorsal simple chaeta, posterior parapodium; (K) compound chaetae, posterior parapodium; (L) ventral simple chaeta. Scale: (A) 0.18 mm; (B) 90 µm; (C,D) 0.24 mm; (E–L) 20 µm.

ETYMOLOGY

The species is named after Dr María Victoria Díaz Castañeda, Mexican polychaetologist, who kindly provided us with the specimen.

TYPE LOCALITY

Six Men's Bay, Barbados Islands.

DISTRIBUTION

Barbados Islands.

HABITAT

In the coral Montastrea annularis; 10 m depth.

TYPE SPECIES

Pionosyllis weismanni Langerhans, Reference Langerhans1879, by present designation.

DIAGNOSIS

Body of macrofaunal to medium size, some species filiform. Without ciliary bands. Segments not fused. Prostomium with two pairs of eyes and two anterior eyespots or without eyes, bearing three antennae and two palps; median antenna inserted near posterior margin of prostomium. Palps fused at their bases, with a dorsal furrow, divergent, triangular in shape. Peristomium with two pairs of tentacular cirri. Antennae, tentacular cirri and dorsal cirri of first chaetiger long, smooth to rugose or pseudoarticulated when very long; remaining dorsal cirri short, exogonid-like, somewhat longer than parapodial lobes. Parapodia without prechaetal lobes. Subcirral papilla absent. Ventral cirri inserted at bases of parapodial lobes, not modified. Compound chaetae heterogomph or hemigomph bidentate falcigers, with moderately long or short bidentate blades; spines on margin short. Dorsal and ventral simple chaetae on posterior parapodia. Ventral simple chaetae enlarged, usually with proximal tooth longer than distal tooth, and provided with a hood. Tips of aciculae acuminate. Pharynx and proventricle similar in length; pharyngeal tooth located on anterior rim. Reproduction by epigamy.

APOMORPHIES

Clade supported by one clear apomorphy: ventral simple chaetae thick and enlarged (character 42, state 1).

ETYMOLOGY

The name of the genus refers to the short dorsal cirri of members of this genus.

KEY TO SPECIES

1. 1. Ventral simple chaetae of similar width to shafts of compound chaetae, with both teeth similar in size, without hood. Compound chaetae heterogomphBrevicirrosyllis gorringensis.

   • Ventral simple chaetae very large, with proximal tooth longer than distal tooth, provided with a hood. Compound chaetae hemigomph2

2. 2. Dorsal cirri with fibrillar inclusions3

   • Dorsal cirri without fibrillar inclusions4

3. 3. Dorsal cirri on chaetiger 2 present … Brevicirrosyllis weismanni

   • Dorsal cirri on chaetiger 2 absent … Brevicirrosyllis mariae

4. 4. Dorsal simple chaeta truncate … Brevicirrosyllis mayteae

   • Dorsal simple chaeta pin-shaped … Brevicirrosyllis ancori

Pionosyllis ancori San Martín & Hutchings, Reference San Martín and Hutchings2006: 324, figure 56A–M.

TYPE LOCALITY

Yonge Reef, Great Barrier Reef, Queensland, Australia.

DISTRIBUTION

Australia (Queensland, Western Australia, New South Wales).

HABITAT

In encrusting algae, 30 m depth.

Pionosyllis gorringensis Hartmann-Schröder, Reference Hartmann-Schröder1977: 86, figures 36–40.

MATERIAL EXAMINED

Holotype ZMUH (P-13681) and (P-13682) (3 paratypes).

REMARKS

This species is poorly known, only known after its original description.

TYPE LOCALITY

Gorringe Bank (east Atlantic).

DISTRIBUTION

Known only from the type locality.

HABITAT

Dredges; 72 m depth.

Pionosyllis mariae San Martín & Hutchings, Reference San Martín and Hutchings2006: 340, figures 46D–F, 70A–J, 71A–F, 72A–C.

TYPE LOCALITY

Yonge Reef, Great Barrier Reef, Queensland, Australia.

DISTRIBUTION

Australia (Queensland and New South Wales).

HABITAT

In encrusting communities and in sand, 9–244 m depth.

Pionosyllis mayteae San Martín & Hutchings, Reference San Martín and Hutchings2006: 344, figure 73A–K.

TYPE LOCALITY

Yonge Reef, Great Barrier Reef, Queensland, Australia.

DISTRIBUTION

Australia (Queensland).

HABITAT

In encrusting communities, 30 m depth.

Pionosyllis weismanni Langerhans, Reference Langerhans1879: 546, pl. 32, figure 11.- Banse, Reference Banse1959: 431, figure 4.- (?) Ben-Eliahu, Reference Ben-Eliahu1977: 50, figure 20.- Hartmann-Schröder, Reference Hartmann-Schröder1977: 85, figure 27–35.- Uebelacker, Reference Uebelacker, Uebelacker and Johnson1984: 67, figure 60. San Martín, Reference San Martín, Ramos, Alba, Bellés, Gosólbez, Guerra, Macpherson, Martin, Serrano and Templado2003: 71, figures 24, 25.

Pionosyllis weissmanni Langerhans, Reference Langerhans1879 [sic].- Campoy, Reference Campoy1982: 337, pl. 27 a–i.-Núñez & San Martín, Reference Núñez and San Martín1996: 209, figure 4f–j.

Pionosyllis pierantoni Cognetti, Reference Cognetti1957: 42–43, figure 8.

REMARKS

This species seems to be very variable (see Ben-Eliahu, Reference Ben-Eliahu1977); it could constitute a complex of species.

TYPE LOCALITY

Madeira (Portugal).

DISTRIBUTION

North-eastern Atlantic, from British Isles to Cape Verde Islands (López & San Martín, Reference López and San Martín1994). Mediterranean Sea. Red Sea. Gulf of México. Cuba.

HABITAT

Calcareous concretions, inside corals, algae, and sand; from intertidal to about 200 m depth.

Nudisyllis Knox & Cameron, Reference Knox and Cameron1970: 77, emended by San Martín & Hutchings, Reference San Martín and Hutchings2006.

TYPE SPECIES

Nudisyllis tinihekea Knox & Cameron, Reference Knox and Cameron1970, by monotypy.

DIAGNOSIS

Body small, fragile, of meiofaunal size. Segments not fused. Prostomium proportionally large, with four eyes and sometimes a pair of anterior eyespots; three antennae, and two palps. Palps separate, free from each other, but close at their bases, triangular to distally rounded in shape. Median antenna inserted on middle of prostomium or on line with lateral antennae. Nuchal organs as two ciliated grooves; cilia extending to laterals of prostomium. Two pairs of tentacular cirri. Dorsal cirri on all chaetigers, long, cylindrical, smooth or slightly rugose. Subcirral papilla absent. Ventral cirri not modified. Compound chaetae with both unidentate and bidentate blades on same parapodium, or all indistinctly bidentate, with unidentate appearance; bidentate blades having proximal tooth very small, similar to a spine; spines on margin short. Tips of aciculae tricuspidate or lancet-shaped. Pharynx small, shorter than proventricle; pharyngeal tooth located near anterior rim, elongated to ovate. Reproduction by epigamy, probably with dorsal incubation of eggs, verified on two species; care of juveniles on dorsal cirri, verified in one species.

APOMORPHIES

Clade supported by three apomorphies: pharynx shorter than proventricle (character 31, state 1), state change is shared with Odontosyllis fulgurans and Neopetitia amphophthalma; pharyngeal tooth elongated, rhomboidal to ovate (character 35, state 1), state change is a parallelism with Salvatoria kerguelensis and Prosphaerosyllis longipapillata; some compound chaetae with proximal tooth small or absent (character 47, state 2), shared with most of the Exogoninae species studied (except Exogone dispar), Palposyllis prosostoma, Westheidesyllis gen. nov., Miscellania dentata and Pionosyllis stylifera. Egg brooding (character 52, state 1) and juveniles attached to female body (character 54, state 1) might be apomorphies of the clade, although the first one is uncertain in Pionosyllis divaricata and Pionosyllis magnidens, and the second one in these two species and in Nudisyllis tinihekea. State change in character 52 is convergent with the examined Exogoninae and Perkinsyllis gen. nov. and that in character 54 is shared with Sphaerosyllis hystrix, Exogone dispar and Brania pusilla. The presence of cilia on lateral margins of prostomium (character 4, state 1) is uncertain in P. magnidens and P. divaricata; if present in these two species it might also be an apomorphy of the clade, shared with Odontosyllis fulgurans, Eusyllis lamelligera and Westheidesyllis gen. nov.

KEY TO SPECIES

1. 1. Parapodia each with compound chaetae provided with bidentate blades dorsally and unidentate blades ventrally 2

   • All blades of compound chaetae indistinctly bidentate, proximal tooth reduced to a small spine3

2. 2. Strong dorsoventral gradation of blade-length of compound chaetae on each parapodium. Dorsal compound chaetae with long, bidentate blades, provided with a few distinct spines basally, ventral compound chaetae with short, smooth, unidentate blades. Pharyngeal tooth less than one third of length of pharynx Nudisyllis pulligera

   • Dorsoventral gradation of blade-length not so strong, all blades on each parapodium similar in length, dorsal blades bidentate and provided with moderate spines, ventral blades unidentate, with short spines on margin. Pharyngeal tooth very long, approximately half length the pharynx Nudisyllis magnidens

3. 3. Parapodia each with 2–3 dorsal tufts of long, distinct ciliaNudisyllis tinihekea

   • Parapodia without tufts of cilia … … Nudisyllis divaricata

Syllis divaricata Keferstein, Reference Keferstein1862: 111, Taf. 9, figures 45–47.

Pionosyllis divaricata Fauvel, Reference Fauvel1923: 287, figure 109 f–i.- Cognetti, Reference Cognetti1957: 39–40.- San Martín, Reference San Martín1990: 591, figure 1; 2003: 85, figure 34.

Non Pionosyllis divaricata Haswell, Reference Haswell1920: 104, pl. 13, figures 2–3.

TYPE LOCALITY

Saint Vaast la Houge, France.

DISTRIBUTION

North-east Atlantic, Mediterranean, Madeira, Cape Verde Islands, Cuba.

HABITAT

Algae, Posidonia oceanica and Thalassia testudinum beds, at few metres depth.

Pionosyllis magnidens Day, Reference Day1953: 416, text-figure 3a–c; 1967: 263, figure 12.8.a–c.

Pionosyllis cf. magnidens Hartmann-Schröder, Reference Hartmann-Schröder1974: 125, Taf. 9–10, figures 82–88.

MATERIAL EXAMINED

Lamberts Bay (shore), Station 204, (BMNH, 1961.16.14/15), Holotype.

DESCRIPTION

Holotype lacking antennae and cirri (Figure 5A), broken, consisting of one anterior part of 13 chaetigers (1.25 mm long), a midbody part of 19 chaetigers, and a posterior part of 15 chaetigers. Prostomium rectangular, with lateral constrictions; two pairs of large eyes in open trapezoidal arrangement. Palps separate, divergent (Figure 5A). Anterior parapodia each with about 20 compound chaetae, midbody parapodia each with about 10–12 chaetae. Compound chaetae provided with bidentate blades dorsally and unidentate blades ventrally, with shorter spines on margin and more distinctly unidentate more ventrally (Figure 5B,D). Slight dorsoventral gradation in length of blades, blades of compound chaetae about 21 µm long above, 16 µm long below on midbody parapodia; blades of dorsalmost compound chaetae bidentate, remaining blades on each fascicle unidentate; bidentate compound chaetae arranged by couples, two couples on anterior parapodia, a single couple on remaining parapodia; unidentate blades with strongly hooked tips. Pharynx very short, everted in holotype, with very long, dagger-shaped pharyngeal tooth, apparently without soft papillae on anterior rim. Proventricle longer than pharynx, extending through about 9 segments, with about 30 muscle cell rows.

Fig. 5.

Nudisyllis magnidens (Day, Reference Day1953) comb. nov. (A) Anterior end with everted pharynx, dorsal view; (B) compound chaetae, anterior chaetiger; (C) aciculae, midbody parapodium; (D) compound chaetae, midbody parapodium (BMNH 1961.16.14/15). Scale: (A) 0.5 mm; (B–D) 20 µm.

REMARKS

Day (Reference Day1953) described and figured this species as having palps fused at bases, while the species has free palps and bidentate compound chaetae (Hartmann-Schröder, Reference Hartmann-Schröder1974), which have been observed in the holotype.

TYPE LOCALITY

Lamberts Bay, South Africa.

DISTRIBUTION

Southern Africa.

HABITAT

In sand on rocks, algae, coralline algae, intertidal and subtidal.

Syllis pulligera Krohn, Reference Krohn1852: 251, figures 1–3.

Pionosyllis pulligera Fauvel, Reference Fauvel1923: 286, figure 109 k–o.- Cognetti, Reference Cognetti1957: 38.- Hartmann-Schröder, Reference Hartmann-Schröder1971: 154.- San Martín, Reference San Martín, Ramos, Alba, Bellés, Gosólbez, Guerra, Macpherson, Martin, Serrano and Templado2003: 82, figures 32, 33.

Pionosyllis serrata Southern, Reference Southern1914: 23, Pls. 3–4, figure 5A–E.- Fauvel, Reference Fauvel1923: 286, figure 109a–e.- Hartmann-Schröder, Reference Hartmann-Schröder1971: 153.- Campoy, Reference Campoy1982: 342.- San Martín, Reference San Martín1984: 111, Lám. 19.

Pionosyllis confusa Hartmann-Schröder, Reference Hartmann-Schröder1960: 92, Taf. 10–11, figures 80–82.

MATERIAL EXAMINED

Many specimens from the Iberian Peninsula, Balearic Islands and Cape Verde Islands. Specimens identified as P. pulligera from ZMUH (P-14689; V-7948), and from MNHN (A 76), unknown data, collector and identifier. Four paratypes of P. confusa (ZMUH, P-14688), Sarso (Red Sea), Gerlach coll.

REMARKS

The specimens from NMHN are in poor condition, but a few dorsal compound chaetae on some parapodia have bidentate blades like other studied specimens which were recorded as Pionosyllis pulligera. These bidentate blades may be difficult to see (likely being overlooked by several authors) or have fallen off in P. pulligera, while they are clearly visible in P. serrata. Thus, we believe that the specimens with clearly visible bidentate blades were reported as P. serrata while the remaining ones were reported as P. pulligera.

Pionosyllis confusa was described as having the pharyngeal tooth in the middle of the pharynx. However, the paratypes have the pharyngeal tooth on the anterior margin and the compound chaetae are identical to those of P. serrata. Besides it has not been possible to observe the holotype; we believe that the original description of the pharyngeal tooth may likely be a misinterpretation. Pierantoni (Reference Pierantoni1905) reported brooding of eggs and development of juveniles on dorsal cirri.

TYPE LOCALITY

Bay of Villafranca, near Nice (France, Mediterranean Sea).

DISTRIBUTION

North-east Atlantic, from the North Sea to Cape Verde Islands. Mediterranean, Black Sea. Red Sea.

HABITAT

Among algae; interstitial in sand. Intertidal and subtidal.

Nudisyllis tinihekea Knox & Cameron, Reference Knox and Cameron1970: 77, figures 6–9.- San Martín & Hutchings, Reference San Martín and Hutchings2006: 281, figure 17A–F.

Pionosyllis pulligera (non Krohn) Augener, Reference Augener1913: 221, Taf. 2, figure 8, text-figure 29.

Pionosyllis samsonensis Hartmann-Schröder, Reference Hartmann-Schröder1980b: 52, Abb. 39–43; Reference Hartmann-Schröder1981: 32; Reference Hartmann-Schröder1982: 65. Reference Hartmann-Schröder1983: 130; Reference Hartmann-Schröder1984: 20; Reference Hartmann-Schröder1985: 69; Reference Hartmann-Schröder1986: 41; Reference Hartmann-Schröder1987: 38; Reference Hartmann-Schröder1991: 35.

MATERIAL EXAMINED

ZMUH (P-17098) (3 specimens), Port Samson, Australia. Australia: see San Martín & Hutchings, Reference San Martín and Hutchings2006.

REMARKS

This species is very similar to other members of the genus. However, it is characterized by having tufts of long, distinct cilia on the parapodia and on the dorsal surface of the body, but not forming rows. The compound chaetae are indistinctly bidentate, the aciculae have lancet-shaped, nearly tricuspidate tips, and dorsal and ventral simple chaetae are unidentate and distally somewhat hooked. Augener (Reference Augener1913) reported dorsal brooding of eggs.

TYPE LOCALITY

Boat Harbour, Snares Islands, New Zealand.

DISTRIBUTION

Australia and New Zealand.

HABITAT

Coarse sand, algae, seagrass, sand with debris. Eulittoral.

TYPE SPECIES

Opisthodonta morena Langerhans, Reference Langerhans1879. Designated by Hartman, Reference Hartman1959.

DIAGNOSIS

Body long, with numerous segments, stout, dorsally convex, of macrofaunal size. Segments not fused. Without ciliary bands. Prostomium provided with two pairs of eyes, sometimes two anterior eyespots, three antennae and two palps. Median antenna inserted on the middle of prostomium or slightly in front of level of anterior eyes. Palps free to each other. Peristomium small, partially covered by prostomium and first chaetiger, with two pairs of tentacular cirri. Dorsal cirri on all chaetigers, cylindrical, long to very long, smooth or slightly rugose. Parapodia slender, elongate; ventral cirri of some species, at least on anterior parapodia, ovate, foliaceous almost completely fused with parapodial lobe, usually provided with hyaline inclusions, perhaps glands. Remaining ventral cirri neither foliaceous nor fused to parapodial lobes, inserted at the bases of parapodia. Chaetal bundles formed of numerous compound chaetae, including falcigers provided with long, thick proximal tooth and short distal tooth and a few chaetae with long, slender, spiniger-like blades; some species with a tendon contacting proximal tooth and blade edge. Dorsal simple chaetae apparently lacking; ventral simple chaeta usually also lacking. Aciculae tips button-shaped, with a crown of spines, acuminate or tricuspidate. Pharynx and proventricle similar in length, usually long. Pharynx with a crown of soft papillae on anterior rim and a single middorsal tooth, placed anteriorly, on anterior third or even in middle part of pharynx.

REMARKS

Opisthodonta differs from Pionosyllis in having separated palps and in the arrangement of the compound chaetae. Pionosyllis species always have the pharyngeal tooth on the anterior pharyngeal margin. Opisthodonta is usually composed of O. morena, O. mitchelli, and O. pterochaeta, but three other species should be incorporated into the genus: a new species mainly differing in the position of the pharyngeal tooth and details of the compound chaetae, and two species in Pionosyllis. Pionosyllis uraga has the pharyngeal tooth on the anterior rim of the pharynx and P. melaenonephra has it slightly behind the rim, on the anterior half of the pharynx. We placed them in Opisthodonta since they have foliaceous anterior ventral cirri fused with the parapodial lobes, and the compound chaetae are clearly of the Opisthodonta type. On the other hand, Opisthodonta pterochaeta Southern, Reference Southern1914 and O. curticirris (Hartmann-Schröder, Reference Hartmann-Schröder1983) should be transferred to other genera (see San Martín, Reference San Martín, Ramos, Alba, Bellés, Gosólbez, Guerra, Macpherson, Martin, Serrano and Templado2003; San Martín & Hutchings, Reference San Martín and Hutchings2006), and the species with a tendon connecting the proximal tooth and blade edge are herein provisionally included in Opisthodonta. It is possible that all these species form a separate group, but most of them are incompletely known as they are rare and have extremely fragile bodies, allowing only to collect fragments. In fact, many specimens of this group have been published without species names, and probably belong to undescribed species. For example, Pionosyllis sp. from Spanish Mediterranean (Campoy, Reference Campoy1982), Pionosyllis sp. C from the Gulf of México (Uebelacker, Reference Uebelacker, Uebelacker and Johnson1984), Eusyllis sp. from Australia in Hartmann-Schröder (Reference Hartmann-Schröder1984), and Pionosyllis divaricata non Keferstein, from Australia (Haswell, Reference Haswell1920).

KEY TO SPECIES

1. 1. Some blades of compound chaetae with a tendon connecting proximal tooth with blade edge2

   • Blades without such tendon7

2. 2. Pharyngeal tooth located near anterior margin of pharynx3

   • Pharyngeal tooth located near middle of pharynx5

3. 3. Blades of compound chaetae from midbody with distal tooth indistinct or non-existentOpisthodonta longocirrata

   • Blades with distal tooth4

4. 4. Dorsalmost blades basally narrow and distally wideOpisthodonta serratisetosa

   • Blades of compound chaetae wider basally than distallyOpisthodonta tridentata

5. 5. Dorsal cirri shorter than body width. Distal tooth of blades of compound chaetae slightly shorter than proximal toothOpisthodonta luquei

   • Dorsal cirri longer than body width6

6. 6. Distal tooth minute and proximal tooth distinctly elongated. Falcigers elongatedOpisthodonta templadoi

   • Distal and proximal tooth similar in size. Falcigers short and wideOpisthodonta rousei

7. 7. Pharyngeal tooth anteriorly located … Opisthodonta uraga

   • Pharyngeal tooth located distinctly back from anterior margin8

8. 8. Falcigers provided with a translucent hood (in fact, several rows of spines) on marginO. russelli

   • Falcigers with a single row of spines on margin9

9. 9. Antennae and anterior cirri rugose to pseudoarticulated. Dorsum of anterior segments with transverse dark rows. With ventral simple chaetaOpisthodonta melaenonephra

   • All appendages smooth. Dorsum not pigmented. Without ventral simple chaeta 10

10. 10. Spiniger-like chaetae very long and slender, more than three times longer than falcigersOpisthodonta hanneloreae

    • Spiniger-like chaetae with shorter bladesOpisthodonta morena and O. mitchelli

Pionosyllis longocirrata Saint-Joseph, Reference de Saint-Joseph1886: 160, pl. 8, figures 24–29.- Fauvel, Reference Fauvel1923: 288, figure 110 h–l.- Cognetti, Reference Cognetti1957: 40.- Day, Reference Day1967: 264, figure 12.8.l–m.

Pionosyllis morenoae San Martín, Reference San Martín1984: 109–111, figure 18.- Núñez & San Martín, Reference Núñez and San Martín1996: 211, figure 4 N–Q.

MATERIAL EXAMINED

MHNP (A-422): numerous specimens; (A-76), 33 specimens (as P. divaricata).

REMARKS

Pionosyllis morenoae was described as having elongate blades with a curved proximal tooth contacting the distal part of blades, and becoming indistinct or absent on compound chaetae from midbody to posterior end (San Martín, Reference San Martín1984). These chaetal types are identical to those of the southern African Pionosyllis longocirrata Saint-Joseph, 1886 reported in Day (Reference Day1967). However, these chaetae are quite different to those described by Saint-Joseph (Reference de Saint-Joseph1886). The MHNP specimens examined agree with P. morenoae (San Martín, Reference San Martín1984). We assume that Saint-Joseph and subsequent authors were not able to observe the delicate details of the distal blade end and considered this material to be conspecific (taking into account that the types are most likely lost).

TYPE LOCALITY

Dinard, France.

DISTRIBUTION

Eastern Atlantic, from English Channel to southern Africa. Western Mediterranean.

HABITAT

Among Laminaria and shells, harbours, Posidonia oceanica beds and leaves, rocks and algae from sublittoral to coraligenous bottoms, calcareous coralline algae, inside sponges, from 0 to 100 m depth.

Opisthodonta hanneloreae San Martín & Hutchings, Reference San Martín and Hutchings2006: 302, figure 37A–G.

TYPE LOCALITY

Wallabi group of Islands, Western Australia.

HABITAT

Dead corals and shell debris, in shallow water.

DISTRIBUTION

Western Australia.

Pionosyllis luquei San Martín, Reference San Martín1990: 598–601, figures 6&7.- Góngora-Garza & de León-González, Reference Góngora-Garza and de León González1993: 20–22, figure 2.

TYPE LOCALITY

Isle of Pines, Cuba.

DISTRIBUTION

South Cuba, María-Madre Island, Nayarit (Pacific coast of México).

HABITAT

Inside coralline rocks; 1 m depth.

Pionosyllis melaenonephra Haswell, Reference Haswell1920: 103, pl. 12, figures 11–16, pl. 13, figure 1.

Opisthodonta melaenonephra San Martín & Hutchings, Reference San Martín and Hutchings2006: 303, figures 38A–G, 39A–O.

MATERIAL EXAMINED

Holotype (AM 494). Australia: see San Martín & Hutchings, Reference San Martín and Hutchings2006.

TYPE LOCALITY

Port Jackson, Sydney, Australia.

DISTRIBUTION

South-western Australia.

HABITAT

Among roots of oarweeds.

Opisthodonta mitchelli Kudenov & Harris, Reference Kudenov and Harris1995: 51, figure 1.18.- Capa et al., Reference Capa, San Martín and López2001: 622.

TYPE LOCALITY

Off Point Arguello, Santa María Basin, California.

MATERIAL EXAMINED

Coiba National Park, Panamanian Pacific: 119 specimens (see Capa et al., Reference Capa, San Martín and López2001).

DISTRIBUTION

California, Panamá.

HABITAT

Soft bottoms and rocky substrata, in depths of 72–111 m (Kudenov & Harris, Reference Kudenov and Harris1995). Inside dead corals at low depth.

Opisthodonta morena Langerhans, Reference Langerhans1879: 547, figure 12.- Pérès, Reference Pérès1954: 107, figures 3–6.- Laubier, Reference Laubier1966: 249.- Storch, Reference Storch1966: 173, pl.1, figure 2.- Hartmann-Schröder, Reference Hartmann-Schröder1971: 100, figures 1–3.- Campoy, Reference Campoy1982: 307.- San Martín, Reference San Martín, Ramos, Alba, Bellés, Gosólbez, Guerra, Macpherson, Martin, Serrano and Templado2003: 54, figures 15&16. San Martín & Hutchings, Reference San Martín and Hutchings2006: 306, figures 40A–F, 41A,F, 42A–B.

HABITAT

Occurring interstitially in coarse and coral sand, seagrasses, mud, from intertidal to depths greater than 240 m (San Martín & Hutchings, Reference San Martín and Hutchings2006).

DISTRIBUTION

Western Atlantic, Mediterranean, Red Sea, Australia (New South Wales, Western Australia).

Pionosyllis rousei San Martin & Hutchings, 2006:345, figure 74A–F.

TYPE LOCALITY

Elisabeth and Middleton Reefs, Australia.

DISTRIBUTION

Only known from the type locality.

HABITAT

Substrate unknown, 244 m depth.

Pionosyllis cf. uraga Day, Reference Day1973: 33, figure 4 k–m.

Pionosyllis uraga Perkins, Reference Perkins1981: 1108 non Pionosyllis uraga Imajima, Reference Imajima1966.

Pionosyllis sp. Gardiner, Reference Gardiner1976: 137.

MATERIAL EXAMINED

Morrocoy National Park (Venezuela), David Bone leg., Holotype (MNCNM 16.01/6063) and 6 paratypes (MNCNM 16.01/6064, 6065, 6066, 6067, 6068 and 6069), Thalassia testudinum beds, 0.5 m depth.

DESCRIPTION

Body long, thick, strongly convex dorsally, without colour markings, very fragile; only anterior fragments, 5.4 mm long, 0.3 wide, for 34 chaetigers (holotype). Prostomium ovate, with two pairs of eyes in open trapezoidal arrangement and two small anterior eyespots; median antenna originating just in front of anterior eyes, cylindrical, longer than prostomium and palps together, lateral antennae shorter than median one, originating on anterior margin of prostomium; palps long and large, broad, folded downwards, separated for their entire length. Two kidney-shaped nuchal organs posterolateral to prostomium (Figure 6A). Two pairs of long tentacular cirri. Antennae, tentacular cirri and dorsal cirri long, cylindrical to thread-like. Dorsal cirri with distinct cirrophores, alternating in length on anterior segments, long cirri much longer than body width, usually coiled and sometimes forming a tangle; short cirri as long as or shorter than body width; several specimens with dorsal cirri shorter than those described above. Parapodia elongate, subtrapezoidal; ventral cirri foliaceous, ovate, fused to parapodial lobe except distally, with dark inclusions (Figure 6B). Compound chaetae similar throughout body, heterogomph, with nearly smooth shafts. Parapodia each including 3–5 compound chaetae with long, spiniger-like blades, tips indistinctly bifid (Figure 6E), and more than 30 falcigers with short distal tooth and long, broad, somewhat curved proximal tooth (Figure 6D); blades of both falcigers and spiniger-like chaetae provided with a translucent hood, slightly spinose on margin, forming a ‘breast’ more distinct ventrally and posteriorly. Anterior parapodia with more compound chaetae than midbody parapodia. Slight gradation on length of falcigers on each fascicle, 30 µm in length dorsally, 20 µm in length ventrally, on midbody parapodia. Simple chaetae not seen. Parapodia each with 2–3 aciculae, ending in small button (Figure 6C). Pharynx long and wide, with crown of 10 soft papillae with cilia on anterior rim; pharyngeal tooth rounded, slightly acute anteriorly, located just in middle of pharynx (Figure 6A). Proventricle somewhat shorter than pharynx, extending through about 11 chaetigers, with about 28 muscle cell rows.

Fig. 6.

Opisthodonta russelli sp. nov. (A) Anterior dorsal view, paratype; (B) anterior parapodium, lateral view; (C) aciculae; (D) falcigers; (E) spiniger-like compound chaetae. Scale: (A) 0.77 mm; (B) 0.15 mm; (C–E) 20 µm.

ETYMOLOGY

The species is dedicated to Dr David E. Russell, who allowed us to describe this species as a new.

REMARKS

This species closely ressembles Opisthodonta uraga. However, all reports of the species consistenly highlighted the pharyngeal tooth located in the middle of pharynx, while O. uraga has a smaller pharyngeal tooth located anteriorly. Furthermore, O. russelli and O. uraga differ in details of the blades of the compound chaetae that the peculiar translucent hoods are more developed in the former than in the later.

DISTRIBUTION

Atlantic coasts of North and South America, from North Carolina to Venezuela.

HABITAT

Thalassia testudinum beds. Coarse to fine or very fine sand, silty sand, from 0.5 m to 189 m depth.

Pionosyllis sp. Baratech & San Martín, Reference Baratech and San Martín1987: 44, figures 4–5.

Pionosyllis serratisetosa López et al., Reference López, San Martín and Jiménez1997: 293–296, figure 1. San Martín, Reference San Martín, Ramos, Alba, Bellés, Gosólbez, Guerra, Macpherson, Martin, Serrano and Templado2003: 89. figures 37&38.

TYPE LOCALITY

Chafarinas Islands (Spain), Alborán Sea (western Mediterranean).

DISTRIBUTION

Only known from the type locality and Alborán Sea.

HABITAT

Among algae, inside block of the coral Cladocora caespitosa; 6–20 m depth.

Pionosyllis templadoi San Martín, Reference San Martín1991b: 17–20, figures 1&2.

TYPE LOCALITY

Isle of Pines and Archipelago of Canarreos, south-west Cuba.

DISTRIBUTION

Only known from the type locality.

HABITAT

Among Halimeda sp., 3 m depth.

Dioplosyllis tridentata Kudenov & Harris, Reference Kudenov and Harris1995: 38, figure 1.12.

REMARKS

Kudenov & Harris (Reference Kudenov and Harris1995) described this species as having a single middorsal tooth, but the crown of papillae and the semi-circle of small teeth on the pharynx opening, characteristic of the genus Dioplosyllis (see Gidholm, Reference Gidholm1962) were absent; thus all characters agree with the diagnosis of Opisthodonta.

TYPE LOCALITY

Off Purísima Point, California.

DISTRIBUTION

Only known from the type locality.

HABITAT

Rocky substrata.

Pionosyllis uraga Imajima, Reference Imajima1966: 114–115, text-figure 37.

Non Pionosyllis uraga Perkins, Reference Perkins1981: 1108.

MATERIAL EXAMINED

Uraga Strait of Tokyo Bay, (NSMNH) holotype. Wakasa Bay (Japan), (IMEO) W-90-42-25, 2 specimens, 126 m depth, sand, 35°57′27″N 135°56′17″E; W-700, 1 specimen, 125 m depth, sand, 36°45′ N 135°5′E; W-541, 1 specimen, 75 m depth, sand, 36°45′135°5′E (Minako Hanaoka leg.).

DESCRIPTION

Only anterior fragments, most dorsal cirri lacking. Body long, stout, with convex dorsum, without colour markings; longest anterior fragment examined from Wakasa Bay, 2.56 mm long, 0.78 mm wide for 26 chaetigers. Prostomium (Figure 7A) ovate to pentagonal, with two small eyes in open trapezoidal arrangement. Dorsal cirri cylindrical, long, slender, smooth, with distinct short cirrophore, alternating dorsal cirri longer than body width and shorter than body width (Figure 7A). Parapodia slender, elongate. Ventral cirri ovate, foliaceous, fused to parapodial lobe on nearly all their length; irregular inclusions inside ventral cirri, perhaps glands (Figure 7B,C). Compound chaetae bundles very dense, composed of numerous chaetae with long, indistinctly bifid spiniger-like blades, and falcigers with proximal tooth longer and thicker than distal tooth, more strongly marked ventrally and posteriorly (Figure 7D). Anterior parapodia each with about 7 spiniger-like compound chaetae and about 60 falcigers; midbody parapodia each with about 3–5 spiniger-like chaetae and about 19 falcigers. Falcigers provided with a short, small, translucent, indistinct hood with short, fine, straight spines on margin. Two aciculae on each parapodium, with blunt tip and crown of subdistal, minute spines (Figure 7E). Pharynx long, surrounded by crown of soft papillae on anterior rim; pharyngeal tooth small, located on anterior margin (Figure 7A,B). Proventricle similar in length to pharynx, with about 40 muscle cell rows.

Fig. 7.

Opisthodonta uraga (Imajima, Reference Imajima1966) comb. nov. (A) Anterior end, dorsal view; (B) anterior end with everted pharynx, ventral view (chaetae not drawn); (C) anterior parapodium, posterior view (dorsal cirrus and chaetae not drawn); (D) spiniger-like compound chaetae of anterior parapodium; (E) spiniger-like from midbody; (F) compound chaetae, midbody parapodium; (G) aciculae. Scale: (A, B) 0.77 mm; (C) 0.15 mm; (D,E) 20 µm.

TYPE LOCALITY

Uraga Strait, Tokyo Bay, Japan.

DISTRIBUTION

Japan. The report of Banse & Hobson (Reference Banse and Hobson1974) of this species for British Columbia and Washington is probably correct.

HABITAT

Sand; from 40 to 150 m depth.

Paraehlersia San Martín, Reference San Martín, Ramos, Alba, Bellés, Gosólbez, Guerra, Macpherson, Martin, Serrano and Templado2003: 61.

TYPE SPECIES

Ehlersia ferrugina Langerhans, Reference Langerhans1881, designated by San Martín (Reference San Martín, Ramos, Alba, Bellés, Gosólbez, Guerra, Macpherson, Martin, Serrano and Templado2003).

DIAGNOSIS

Body long, stout, with numerous segments, of medium to macrofaunal size, dorsally convex. Segments not fused. Double dorsal row of cilia on dorsum of most segments. Prostomium provided with four eyes and a pair of anterior eyespots, three antennae and two palps. Median antenna inserted in the middle of prostomium. Palps fused at bases, with a dorsal furrow, triangular in shape. Nuchal organs as two ciliated grooves. Two pairs of tentacular cirri. Antennae, tentacular cirri and anterior dorsal cirri of adults articulated to irregularly articulated depending upon size, remaining dorsal cirri smooth. Parapodia without prechaetal lobes; most species with digitiform, retractile papilla between parapodial lobes and dorsal cirri of anterior parapodia. Compound chaetae heterogomph, including one or more chaetae with spiniger-like blades and several bidentate falcigerous blades, anteriorly with both teeth similar, posteriorly with proximal tooth longer and more robust than distal tooth; spines on margin of blades short to moderate. Aciculae acuminate. Pharynx and proventricle of similar size. Pharyngeal tooth anteriorly located. Reproduction by epigamy.

APOMORPHIES

Clade supported by a very clear apomorphy, the presence of a subcirral papillae (character 27, state 1). Four other apomorphies can be considered. The dorsal surface of segments is ciliated (character 6, state 1); this state change is shared with Ophiodromus flexuosus and is a homoplasy with most examined Autolytinae (except Proceraea picta), Odontosyllis fulgurans, Dioplosyllis cirrosa, Westheidesyllis gen. nov., Eusyllis lamelligera and Perkinsyllis gen. nov. The dorsal ciliary bands are double (character 7, state 1), a convergence with Epigamia alexandri and all the species of Perkinsyllis gen. nov. except Pionosyllis longisetosa. The antennae are articulated (character 13, state 1), a homoplasy with the examined Syllinae, Eusyllis lamelligera, Opisthodonta melanonaephra and Pionosyllis dionisi, and so are the tentacular cirri (character 14, state 1), a character state shared with the same taxa plus Ophiodromus flexuosus. The dorsal cirri are articulated in anterior segments and smooth in posterior ones (character 15, state 1), a homoplasy with Amblyosyllis sp., Pionosyllis marquesensis, Pionosyllis procera, Eusyllis lamelligera, Westheidesyllis gen nov., Opisthodonta melanonaephra and Pionosyllis dionisi. Finally, the spiniger-like chaetae (character 46, state 1) is a homoplasy with Exogone dispar, Pionosyllis anophthalma, Pionosyllis augeneri, Pionosyllis longisetosa, Pionosyllis spinisetosa, Pionosyllis hartmannschroederae, Pionosyllis dionisi, the examined species of Opisthodonta.

REMARKS

Ehlersia Quatrefages, 1866 is a synonymy of Syllis Lamarck, 1818 (see San Martín, Reference San Martín, Ramos, Alba, Bellés, Gosólbez, Guerra, Macpherson, Martin, Serrano and Templado2003); the type species of Ehlersia is Syllis sexoculata, a species not related to Ehlersia ferrugina, as Ehlersia could not be used, and San Martín (Reference San Martín, Ramos, Alba, Bellés, Gosólbez, Guerra, Macpherson, Martin, Serrano and Templado2003) proposed Paraehlersia as the new generic name.

Pionosyllis dionisi is included in Paraehlersia since the antennae, tentacular and anterior cirri are articulated, and it has spiniger-like compound chaetae. However, its position in the consensus is isolated, and it does not show clear relationships with any other clade. Examination under SEM (San Martín, Reference San Martín, Ramos, Alba, Bellés, Gosólbez, Guerra, Macpherson, Martin, Serrano and Templado2003) revealed neither subcirral papillae nor ciliary bands, but a more detailed examination seems to be necessary.

KEY TO SPECIES

1. 1. Blades of falcigerous chaetae with both teeth similar in size.Paraehlersia (?) dionisi

   • Blades of falcigerous chaetae (from midbody) with proximal tooth distinctly longer than distal one. Anterior parapodia each with subcirral, retractile papilla2

2. 2. Ventral simple chaetae enlarged, with proximal tooth much longer than distal tooth and long subdistal spines. Falcigerous chaetae with blades provided with moderately long, distal spines on marginParaehlersia weissmannioides

   • Ventral simple chaetae not enlarged, without long distal spines. Blades of compound chaetae with short spines on margin3

3. 3. Small size (6 mm long); only most anterior dorsal cirri articulatedParaehlersia articulata

   • Large size (up to 10 mm); large specimens with articulated dorsal cirri on about first anterior third of body. 4

4. 4. Blades of compound chaetae of most posterior parapodia enlargedParaehlersia ehlersiaeformis

   • Blades not enlargedParaehlersia ferrugina

• Pionosyllis articulata Kudenov & Harris, Reference Kudenov and Harris1995: 55, figure 20. Capa et al., 201: 622.

• Paraehlersia articulata Aguado & San Martin, 2006: 6.

REMARKS

This species is very similar to P. ferrugina. Specimens from Coiba Island are smaller than the Mediterranean species, and are provided with ciliary bands and subcirral papilla on each anterior parapodia. Nevertheless the antennae, tentacular cirri, and anteriormost dorsal cirri are weakly articulated, while the cirri of P. ferrugina have with more distinct articles.

TYPE LOCALITY

Santa María Basin (California), USA.

DISTRIBUTION

Southern to central California. Recently, we have examined specimens of this species collected in Coiba Island (Pacific, Panamá). Ehlersia sp. (Westheide, Reference Westheide1974) from the Galápagos Islands probably belongs to this species.

HABITAT

Soft bottoms and rocky substrata, in depths of 60–205 m (Kudenov & Harris, Reference Kudenov and Harris1995). Inside dead corals.

Pionosyllis dionisi Núñez & San Martín, Reference Núñez and San Martín1991: 236, figure 1.- Parapar et al., Reference Parapar, San Martín, Urgorri and Besteiro1993: 372, figure 5. San Martín, Reference San Martín, Ramos, Alba, Bellés, Gosólbez, Guerra, Macpherson, Martin, Serrano and Templado2003: 67, figures 22&23.

Pionosyllis elephantensis Hartmann-Schröder & Rosenfeldt, Reference Hartmann-Schröder and Rosenfeldt1992: 98–99, figures 28–33.

MATERIAL EXAMINED

Several specimens from the Canary Islands and Western Mediterranean. The paratype of P. elephantensis (ZMH P-20750) has been examined for comparison.

TYPE LOCALITY

Candelaria, Tenerife (Canary Islands, Spain).

DISTRIBUTION

Canary Islands, Ceuta (Spain); Elephant Island (South Shetlands, Antarctica).

HABITAT

Biocenosis of Dendrophyllia ramea, coarse sand, silt with stones; 43.5–466 m.

Pionosyllis ehlersiaeformis Augener, Reference Augener1913: 225, figures 31&32.

Paraehlersia ehlersiaeformis San Martín & Hutchings, Reference San Martín and Hutchings2006: 309, figures 43D–F, 44A–K, 45A–F, 46A–C.

MATERIAL EXAMINED

Australia. See San Martín & Hutchings, Reference San Martín and Hutchings2006. ZMH, V 8786 (1 specimen).

REMARKS

A redescription of this species is provided in San Martín & Hutchings (Reference San Martín and Hutchings2006). One specimen in ZMH V 7950 belongs to another species, similar to Perkinsyllis augeneri.

TYPE LOCALITY

Sharks Bay, Western Australia.

DISTRIBUTION

Australia: Western Australia, South Australia, New South Wales. The reports from south-west Africa and Cape Agulhas (South Africa) (Day, Reference Day1953, Reference Day1967) are doubtful.

HABITAT

Pelagic and interstitial in the surf area. Abundant on algae, coralline concretions and seagrasses. Intertidal up to 100 m depth.

Ehlersia ferrugina Langerhans, Reference Langerhans1881: 104, figure 10.- Laubier, Reference Laubier1968: 85.- San Martín, Reference San Martín1984: 306, figures 73&74.

Syllis (Ehlersia) ferrugina Fauvel, Reference Fauvel1923: 269, figure 100 k–u.-Núñez & San Martín, Reference Núñez and San Martín1996: 207–208.

Paraehlersia ferrugina San Martín, Reference San Martín, Ramos, Alba, Bellés, Gosólbez, Guerra, Macpherson, Martin, Serrano and Templado2003: 61, figures 19–21.

TYPE LOCALITY

Puerto de la Orotava (=Puerto de la Cruz), Tenerife Island, Canary Islands, Spain.

DISTRIBUTION

Apparently cosmopolitan in tropical and temperate waters; however, this taxon could be a complex of species.

HABITAT

Very common on algae, Posidonia oceanica and Cymodocea nodosa beds, coraligenous concretions, sand; intertidal to about 100 m depth.

Pionosyllis weissmannioides Augener, Reference Augener1913: 223, figure 30.

Paraehlersia weissmannioides San Martín & Hutchings, Reference San Martín and Hutchings2006: figures 47A–I, 48A–F, 43A–C, 49D–F.

MATERIAL EXAMINED

Sharks Bay, Useless Inlet, Australia, 7 m depth (Holotype, ZMH V-7949). Australia: See San Martín & Hutchings, Reference San Martín and Hutchings2006.

REMARKS

A redescription of this species is provided in San Martín & Hutchings (Reference San Martín and Hutchings2006).

TYPE LOCALITY

Sharks Bay, Useless Inlet, Western Australia.

DISTRIBUTION

Australia: Western Australia, New South Wales.

HABITAT

On sand and shelly grit, shallow waters up to 15 m depth.

TYPE SPECIES

Pionosyllis longisetosa Hartmann-Schröder, Reference Hartmann-Schröder1965 by present designation.

DIAGNOSIS

Body long and slender, of medium to meiofaunal size. Segments not fused. Anterior segments with a single dorsal row of cilia, double after proventricular segments. Prostomium with four eyes and two anterior eyespots or without eyes, with three antennae and two palps. Nuchal organs as two ciliated grooves. Median antenna inserted on middle of prostomium or on posterior margin. Palps fused at bases, with a dorsal furrow, triangular in shape. Two pairs of tentacular cirri. Antennae, tentacular and dorsal cirri long to very long, slender, thread-like, all similar, sometimes coiled over dorsum. Subcirral papilla absent. Two kinds of heterogomph compound chaetae, one provided with slender and spiniger-like, sometimes with very long blades, the other with shorter, elongate falcigers provided with long, fine, distally dressed spines on margin; some species having short spiniger-like blades or lacking. Dorsal and ventral simple chaetae on posterior parapodia. Aciculae distally expanded, bilobed. Parapodia without prechaetal lobes, or with very small ones. Pharynx and proventricle similar in size, or pharynx longer than proventricle. Pharyngeal tooth anteriorly located. Reproduction unknown on most species; however, one specimen of P. hartmannschroederae nom. nov., examined by G.S.M. at the Australian Museum, had attached eggs, ventrally brooded, and is proved a similar reproduction in P. augeneri; perhaps all species of Perkinsyllis brood eggs.

APOMORPHIES

Clade supported by one clear autapomorphy, the presence of some chaetae bearing proximal spines distinctly longer than distal ones (character 49, state 1). Some other apomorphies for the clade might be considered. The dorsal surface is ciliated (character 6, state 1). The state change, which is uncertain for Pionosyllis homocirrata and Pionosyllis spinisetosa, is shared with Ophiodromus flexuosus and a homoplasy with most examined Autolytinae (except Proceraea picta), Odontosyllis fulgurans, Dioplosyllis cirrosa, Westheidesyllis gen nov., Eusyllis lamelligera and Paraehlersia. The aciculae have rounded tips (character 39, state 2), a state change shared with Exogone dispar, Brania pusilla, and Westheidesyllis gen. nov. Details on reproduction are only known from Pionosyllis augeneri and Pionosyllis hartmannschroederae, in which the eggs are brooded (character 52, state 1) attached to the ventral surface of the body (character 53, state 1). If they proved to be present in the remainder of the species within the clade, they could be considered also apomorphies of the genus; change in character 52 would be a homoplasy with Nudisyllis tinihekea, Pionosyllis pulligera and all the studied Exogoninae species, and change in character 53 would be shared with Sphaerosyllis hystrix, Exogone dispar and Brania pusilla.

ETYMOLOGY

The genus is named in honour of Dr Thomas H. Perkins, for his important contributions to the knowledge of the family Syllidae and other polychaetes.

KEY TO SPECIES

1. 1. Small (up to 1.6 mm long). Dorsal cirri absent on chaetiger 2Perkinsyllis homocirrata

   • Body of mid-size to macrofaunal. Dorsal cirri present on chaetiger 22

2. 2. Anteriormost parapodia with compound chaetae similar, provided with short blades3

   • Anteriormost parapodia with compound chaetae provided with blades of different sizes, some of them spiniger-like chaetae4

3. 3. Anteriormost parapodia with compound chaetae provided with distinctly large, broad shafts, and blades with coarse spines on marginPerkinsyllis serrata

   • Anteriormost parapodia without distinctly enlarged shafts on compound chaetae; spines of blades thinPerkinsyllis koolalya

4. 4. Blades of compound chaetae of anteriormost parapodia with coarse spines on margin5

   • Blades of compound chaetae similar throughout, with fine spines on margin6

5. 5. Blades of anteriormost compound chaetae all similar, with elongated blades, with dorsoventral gradation. Spiniger-like chaetae from midbody apparently unidentatePerkinsyllis augeneri

   • Compound chaetae including bidentate spiniger-like chaetae from anteriormost segments. Perkinsyllis longisetosa

6. 6. Falcigers of midbody provided with a double curvature7

   • Blades of compound chaetae with ‘normal’ curvaturePerkinsyllis spinisetosa

7. 7. Dorsal simple chaetae unidentate, with coarse spines on marginPerkinsyllis hartmannschroederae nom. nov.

8. 4. Dorsal simple chaetae bidentate, with thin spines on marginPerkinsyllis anophthalma

Pionosyllis anophthalma Capaccioni & San Martín, Reference Capaccioni and San Martín1989: 41–47, figures 1–3. San Martín, Reference San Martín, Ramos, Alba, Bellés, Gosólbez, Guerra, Macpherson, Martin, Serrano and Templado2003: 76, figures 28&29.

TYPE LOCALITY

Alfaque Inlet, delta of Ebro River, Mediterranean, Spain.

DISTRIBUTION

Only known from the type locality.

HABITAT

Fine sand.

Pionosyllis augeneri Hartmann-Schröder, Reference Hartmann-Schröder1979: 98, figure 119.- San Martín & Hutchings, Reference San Martín and Hutchings2006: 326, figures 57A–J, 58A–F.

(?)Pionosyllis augeneri Hartmann-Schröder, Reference Hartmann-Schröder1980a: 393, figures 10–15.

MATERIAL EXAMINED

ZMUH P-16796 (16 specimens). Australia: See San Martín & Hutchings, Reference San Martín and Hutchings2006.

TYPE LOCALITY

Broome (Australia).

DISTRIBUTION

North-western Australia. Caribbean Sea (?).

HABITAT

Coarse sand and silt. Sediments on mangrove forests.

REMARKS

This species has been re-described by San Martín & Hutchings (Reference San Martín and Hutchings2006). The record of the West Indies could be another species, since there are significant differences in the simple chaetae.

Typosyllis (Langerhansia) longisetosa Hartmann-Schröder, Reference Hartmann-Schröder1990: 49–50, figures 9–12.

Pionosyllis hartmannschroederae San Martín & Hutchings, Reference San Martín and Hutchings2006:330, figure 61A–F.

TYPE LOCALITY

Brisbane (Queensland, Australia).

DISTRIBUTION

Australia (Queensland, Western Australia).

HABITAT

Sandflats in mangroves, dead corals, fine sediment, sediments trapped in algae; intertidal and shallow waters.

Eusyllis homocirrata Hartmann-Schröder, Reference Hartmann-Schröder1958: 235, pl. 38, figures 8–11.-Westheide, Reference Westheide1974: 71, figure 32.

Pionosyllis homocirrata Ding & Westheide, Reference Ding and Westheide1997: 284, figure 5.-Núñez et al., Reference Núñez, Riera, Brito and Pascual2001: 62, figure 1.

TYPE LOCALITY

Bimini Islands.

DISTRIBUTION

Circumtropical: Bimini Islands, Galápagos Islands, India, South China, Cuba, Bahamas, Angola, Canary Islands.

HABITAT

Interstitial on exposed intertidal tropical and subtropical beaches.

Pionosyllis longisetosa Hartmann-Schröder, Reference Hartmann-Schröder1965: 118, figures 80–83.

MATERIAL EXAMINED

Holotype, ZMUH P-14692 and paratype, P-14685.

ADDITIONS TO THE DESCRIPTION

Both specimens incomplete. Anteriormost parapodia with elongated, spiniger-like compound chaetae, with bidentate blades, about 120 µm and coarse serration on margin (Figure 8A), remaining chaetae similar, but shorter, with small proximal tooth, and a distinctly long distal spine (Figure 8B), with dorsoventral gradation in length, 81 µm above, 45 µm below. From midbody backwards, few spiniger-like chaetae on each parapodium but having very long blades (more than 200 µm long), bidentate, with long, fine distal spines (Figure 8C); falcigers with bidentate blades, provided with long, coarse basal spines distally dressed, and 1–2 distal spines long and fine (Figure 8D); shorter blades with short, coarse spines (Figure 8E), and dorsoventral gradation in length, 57 µm above, 32 µm below.

Fig. 8.

Perkinsyllis longisetosa (Hartmann-Schröder, Reference Hartmann-Schröder1965) comb. nov. (HZMP-1996). (A) Spiniger-like compound chaeta, anterior parapodium; (B) compound chaetae, anterior parapodium; (C) distal end of spiniger-like compound chaeta, midbody parapodium; (D) compound chaetae, midbody parapodium; (E) ventralmost compound chaeta, midbody parapodium. Scale: 20 µm.

REMARKS

The blades of compound chaetae appear to have an indistinct second row of spines, which are difficult to observe and could be an artefact.

TYPE LOCALITY

Quedal (Chile).

DISTRIBUTION

From Punta Lavapié to Quedal (Chile).

ECOLOGY

Fine sand with detritus, silt, algae. 20 m to 260 m depth.

Eusyllis serrata Hartmann-Schröder, Reference Hartmann-Schröder1984: 18, figures 23–26.

Pionosyllis serrata San Martín & Hutchings, Reference San Martín and Hutchings2006: 346, figures 72D–F, 75A–N, 76A–F, 77A–F.

MATERIAL EXAMINED

Australia: See San Martín & Hutchings, Reference San Martín and Hutchings2006.

REMARKS

This species is re-described in San Martín & Hutchings (Reference San Martín and Hutchings2006).

TYPE LOCALITY

Goode Beach, Frenchman Bay, Albany (Western Australia).

DISTRIBUTION

Australia (Western Australia, New South Wales).

HABITAT

Posidonia, sand, 1.5–30 m depth.

Pionosyllis sp. A Uebelacker Reference Uebelacker, Uebelacker and Johnson1984: 72–73, figure 66.

Pionosyllis spinisetosa San Martín, Reference San Martín1990: 592, figures 2&3.- Núñez & San Martín, Reference Núñez and San Martín1996: 209, figure 4a–e.

TYPE LOCALITY

Gulf of México, 29°54′ 58.6″N 86° 4′ 58.5″W.

DISTRIBUTION

Gulf of México, Cuba, Canary Islands, Cape Verde Islands.

HABITAT

Sand and mud, inside sponges on Rhizopora mangle roots, green algae; intertidal to 37 m depth.

Pionosyllis Malmgren, Reference Malmgren1867: 158.

Hesiosyllis Wesenberg-Lund, Reference Wesenberg-Lund1950: 14.

TYPE SPECIES

Pionosyllis compacta Malmgren, Reference Malmgren1867 by monotypy.

DIAGNOSIS

Body long to moderately long, stout, of macrofaunal size, dorsally strongly convex. Apparently without ciliary bands. Segments not fused. Prostomium provided with four eyes, sometimes also a pair of eyespots, with three antennae and two palps; sometimes two peristomial cheeks or lobes on large specimens. Median antenna inserted in the middle of prostomium. Palps fused at bases, with a dorsal furrow, triangular in shape. Nuchal organs as ciliated grooves. Two pairs of tentacular cirri. Antennae, tentacular cirri and dorsal cirri smooth, sometimes rugose, long, filiform, similar throughout or alternating slightly in length. Subcirral papilla absent. Ventral cirri not fused to parapodial lobes, proximally inserted; those of anteriormost parapodia inflated, more or less spherical. Heterogomph compound chaetae with bidentate falcigerous blades, the two teeth similar in size; some dorsal anterior falcigers somewhat longer than the remaining in some species; other species with some unidentate blades. Dorsal and ventral simple chaeta on some posterior parapodia, bidentate, with both teeth similar; one species with filiform, unidentate dorsal simple chaeta; spines on margin of blades short to moderate. Aciculae straight, pointed, acute, usually protruding from parapodial lobes. Parapodia with prechaetal lobes. Pharynx and proventricle similar in size. Pharyngeal tooth anteriorly located. Reproduction by epigamy.

APOMORPHIES

Clade supported by one autapomorphy: spherical, inflated ventral cirri on anterior segments (character 22, state 2). Other apomorphies of the clade are the presence of a prechaetal lobe (character 28, state 1), a state change shared with Ophiodromus flexuosus, Pisione longispinulata, Pionosyllis marquesensis, Pionosyllis procera, Amblyosyllis sp. and Basidiosyllis gen. nov.; and the aciculae protruding from the parapodial lobe (character 38, state 1), a state change which is a convergence with Syllis variegata, Trypanosyllis zebra, Amblyosyllis sp., Paraehlersia articulata, Pionosyllis yolandae, Pionosyllis aciculata and Palposyllis prosostoma.

REMARKS

Some of these species are morphologically similar to Syllis corruscans Haswell, Reference Haswell1886, but this species reproduces by schizogamy (Haswell Reference Haswell1920; personal observation) and most likely belongs to the Syllinae. All species of Pionosyllis sensu stricto inhabit muddy sediments in cold waters, polar and subpolar seas or deep bottoms (more than 100 m).

KEY TO SPECIES

1. 1. Ventral cirri of chaetiger 1 laminarP. compacta

   • Ventral cirri of chaetiger 1 not laminar2

2. 2. Compound chaetae all with bidentate blades3

   • Some blades unidentateP. stylifera

3. 3. Blades of posterior compound chaetae with both teeth rounded, convergentP. gigantea

   • Blades of posterior compound chaetae with both teeth acute, divergent4

4. 4. Blades of the compound chaetae all short, bidentate … 5

   • Blades of the compound chaetae with dorsoventral gradation6

5. 5. Blades of compound chaetae with short spines on marginP. magnifica

   • Blades of compound chaetae with moderately long spines on marginP. petalecirrus

6. 6. Some posterior compound chaetae (the most ventral ones) with short blades, with proximal tooth far from the distal one, near the middle of the bladeP. kerguelensis

   • All posterior compound chaetae with similar, moderately long bladesP. enigmatica

Pionosyllis compacta Malmgren, Reference Malmgren1867: 40, figure 48.- Pettibone, Reference Pettibone1954 (in part): 262, figure 28j.- Hartmann-Schröder, Reference Hartmann-Schröder1971: 153 (key), 154.- Uschakov, Reference Uschakov1955: 166, figure 54i–j.

Not Pionosyllis compacta Langerhans, Reference Langerhans1879: 545, figure 10a–e (=Pionosyllis lamelligera Saint-Joseph, 1886, see Núñez & Talavera, Reference Núñez and Talavera1995: 517).

MATERIAL EXAMINED

Arctic Ocean: Spitzbergen, 80°N 13°E, 1 June 1861, coll. Malmgren (syntypes, SMNH 2443). Off Point Barrow, Alaska, 15 miles from shore, 145 m depth, 6 September 1949 (1 ant. end, USNM 21955). All the syntypes are broken, fragmented and in poor condition. A lectotype has been designated and isolated in a vial. The remaining specimens (paralectotypes) are conspecific with the lectotype.

DESCRIPTION

Body moderately long, slender, fragile, with well defined segments (Figure 9A), white to yellowish in alcohol. Body subcylindrical, ventrally flattened, dorsally convex, 8–10 mm long (according to Malmgren, Reference Malmgren1867), 0.8–1 mm wide. Lectotype an anterior fragment 0.8 mm wide and 2.5 mm long for 20 chaetigers. Prostomium (Figure 9A,C) subpentagonal, twice wider than long, with rounded posterior margin; four large lensed eyes in trapezoidal arrangement and usually two anterior eyespots; anterior eyes somewhat larger than posterior ones. Antennae, tentacular cirri and dorsal cirri similar in shape, smooth, without articulations, thick, distally blunt (Figure 9A,D); antennae and tentacular cirri as long as body width or shorter, most lacking on examined specimens; antennae and dorsal tentacular cirri somewhat longer than dorsal cirri, according to Malmgren (Reference Malmgren1867: figure 48). Palps somewhat longer than prostomium, broad, fused at their bases, with a dorsal furrow, widely separated on distal end (Figure 9A–C). Peristomial ring shorter than the following segments, dorsally covered by first segment (Figure 9A). Dorsal cirri alternating, long ones somewhat longer than body width, shorter ones as long as half body width. Ventral cirri of first chaetiger enlarged, stout, foliaceous, rounded (Figure 9B); remaining ventral cirri conical, shorter than parapodia, thickened at their bases and distally pointed (Figure 9D–F). Parapodia each provided with two lobes; prechaetal lobe conical, postchaetal lobe foliaceous and larger than prechaetal one; prechaetal lobe less prominent in posterior chaetigers (Figure 9D–F). Compound chaetae heterogomph falcigers; shafts on anterior chaetigers provided with inconspicuous subdistal spines or smooth, those on midbody and posterior chaetigers with short subdistal serrations; blades bidentate, distal tooth hooked, less curved on anterior compound chaetae than on posterior ones, proximal tooth similar in size to distal one; parapodia each with 1–2 dorsal compound chaetae provided with elongate, slender blades, distally bidentate, longer on anterior and midbody parapodia, about 70 µm in length (Figure 10A), posteriorly shorter, about 41 µm in length, and provided with larger distal teeth (Figure 10E); remaining chaetae on each fascicle, heterogomph falcigers (Figure 10C,F) with strongly bidentate tipped blades, about 47 anteriorly and 15 posteriorly, very similar in length (33 µm anteriorly, 20 µm posteriorly); blades of anterior compound chaetae with close distal teeth (Figure 10A,B); all blades provided with fine, short, distally directed spines on edge. Epitokous forms with bundles of capillary notochaetae and notoaciculae first occurring on chaetigers 12–15 (Figure 9E,F). Dorsal and ventral simple chaetae not seen. Anterior parapodia each with 3 aciculae, straight, pointed distally, provided with a small mucro at the tip, protruding from anterior lobe; mid-posterior parapodia each with 2 similar aciculae (Figure 10D). Pharynx wide, usually everted on preserved specimens, extending through about 3–4 chaetigers when retracted, with a distal crown of 10 soft small lobes; pharyngeal tooth conical to oval, with rounded base, located anteriorly (Figure 9A–C). Proventricle somewhat longer and wider than pharynx, barrel-shaped, extending through about 10 chaetigers, with approximately 28 muscle cell rows (Figure 9A).

Fig. 9.

Pionosyllis compacta Malmgren, Reference Malmgren1867. (A) Anterior end, dorsal view, lectotype (SMNH 2443); (B) anterior end, ventral view, paralectotype (SMNH 2443); (C) prostomium and pharynx, dorsal view (USNM 21955); (D) anterior parapodium, long dorsal cirri, anterior view (SMNH 2443); (E) midbody parapodium, anterior view (SMNH 2443); (F) posterior parapodium, anterior view (SMNH 2443) (neurochaetae and dorsal cirri, not drawn in E, F). Scale: (A,F) 0.14 mm; (B,C) 0.26 mm; (D,E) 0.13 mm.

Fig. 10.

Pionosyllis compacta Malmgren, Reference Malmgren1867. (A) Dorsalmost compound chaeta with elongate blade, anterior parapodium; (B) falcigers, anterior parapodium; (C) falcigers, midbody parapodium; (D) aciculae, midbody parapodium; (E) dorsalmost compound chaeta with elongate blade, posterior parapodium; (F) falcigers, posterior parapodium (A-F: SMNH 2443). Scale: 20 µm.

REMARKS

Langerhans (Reference Langerhans1879; figure 10a–e) reported this species from Madeira but having chaetae very different from those of the types, thus we assume that he likely found another species. Uschakov (Reference Uschakov1955) reported this species from the Bering Sea, listed the characters in a key, and noted that it had ‘anterior part of body bearing dorsally narrow dark transverse striations’; Malmgren also described a similar colour pattern in his original description, but this colour pattern is no longer visible. One of the two specimens from Point Barrow (Alaska) (Pettibone, Reference Pettibone1954) perfectly fits Malmgren's description, but the other one belongs to Nudisyllis.

TYPE LOCALITY

Spitzbergen.

DISTRIBUTION

Arctic (Spitzbergen, Alaska), Bering Sea (Bering Island, Bering Strait).

HABITAT

In low water to 145 m depth.

Hesiosyllis enigmatica Wesenberg-Lund, Reference Wesenberg-Lund1950: 14, pl. 3 figure 16, pl. 4 figure 17.- Fauchald Reference Fauchald1977: 73 (key), 76, 84.

Pionosyllis enigmatica San Martín, Reference San Martín, Ramos, Alba, Bellés, Gosólbez, Guerra, Macpherson, Martin, Serrano and Templado2003: 73, figures 26&27.

MATERIAL EXAMINED

North-eastern Atlantic: east of Iceland, 65°00′N 11°16′W, 584 m, 20 May 1896, ‘Ingolf’ Station 59 (holotype of Hesiosyllis enigmatica: 1 ant. end, female + 2 middle fragments in alcohol; 2 slides in gum chloral: 10th right + 11th left parapodia, ZMUC-POL-16); off western Sweden: Björns Rev, Koster Fjord, 90–130 m, 6 December 1985, coll. F. Pleijel (1 ant. end + 2 fragments, as Pionosyllis sp., det. FP; ZMUC-POL-17; 3 ant. ends, as Pionosyllis sp., det. FP; IDENTICHAET); North Sea: Helgoland, (1 ant. end as Pionosyllis compacta, det. Augener Reference Augener1924, ZMH V-9771). Bank of Galicia (north-western Spain) (3 anterior fragments), among Madrepora oculata, 760–769 m depth (Fauna Ibérica II Cruise).

DESCRIPTION

Body long, massive, opaque, fragile, without colour markings (preserved specimens), dorsally convex, flattened ventrally, with well defined segments (Figure 11A–D); holotype 6.5 mm long, 2 mm wide for 21 chaetigers, 2 fragments not included; largest examined specimen (ZMH V-9771) 31 mm long, 1.5 mm wide for 90 chaetigers. Prostomium squared to round, somewhat wider than long; a median dorsal cleft dividing prostomium into lobe or cheek on each side; four lensed eyes in trapezoidal arrangement, anterior pair slightly larger than posterior pair (Figure 11A,C,E). Antennae, tentacular and dorsal cirri similar in shape along the whole body, long, slender, thin, smooth (Figures 11A,C,D, 12C,D). Median antenna originating between posterior pair of eyes, twice as long as lateral ones; lateral antennae originating in front of anterior pair of eyes, somewhat longer than prostomium and palps together (Figure 11A,C). Palps long, broad, divergent, basally fused, with a median dorsal furrow, slightly longer than prostomium. Peristomium short, partially covered by the dorsal lobes of prostomium and first chaetiger; dorsal tentacular cirri similar in length to median antenna, about 2–3 times longer than ventral ones. Dorsal cirri alternating long and short, long cirri about 3 times longer than body width, shorter cirri as long as body width (Figure 11A,C,D); ventral cirri somewhat shorter than parapodial lobes, thick and rounded anteriorly (Figures 11B,D, 12A) and ovate, pointed posteriorly (Figure 12C,D). Parapodia provided with prechaetal and postchaetal lobes; prechaetal lobe conical, distally pointed, postchaetal lobe rounded and shorter than prechaetal one (Figures 11A,C, 12A–D). Compound chaetae numerous, 40–50 on each anterior parapodium, progressively decreasing to about 5 posteriorly; all heterogomph falcigers, dorsalmost one provided with long, slender, minutely bidentate blade with numerous fine, short spines on edge (Figures 12B, 13A,E); shafts provided with short subdistal spines. Blades of remaining chaetae more strongly bidentate, all similar in shape, with coarse, distally directed, uniform spines on edge, distal tooth hooked, proximal tooth similar in shape and size to distal one (Figures 13B,F,G, 14A–E), except for dorsalmost blades on midposterior chaetigers, with proximal tooth smaller than distal one (Figure 13E). Slight dorsoventral and anteroposterior gradation in length of blades, articles progressively becoming shorter and slightly wider posteriorly; dorsalmost blades of compound chaetae in holotype about 140 µm long, ventralmost ones about 114 µm long on anterior parapodia; blades about 128 µm long dorsally, 74 µm ventrally on posterior parapodia (chaetiger 59, ZMH V:9771). Simple chaetae only found on last chaetiger of one specimen (ZMH V-9771); solitary dorsal simple chaeta slender, bidentate, with faint spines on margin (Figure 13C); solitary ventral simple chaeta somewhat thicker than dorsal one, bidentate, slightly curved, with faint serration distally (Figure 13D). Anterior parapodia each with 5–8 straight, thick, distally pointed aciculae (Figure 14F); number of aciculae per parapodium decreasing progressively posteriorly (Figure 13G), posterior parapodia each with 1–2 aciculae of same type as anterior ones (Figure 14H). Pharynx wide, usually everted on examined specimens, extending through 8 chaetigers, provided with 10 large, triangular, soft lobes surrounding opening (Figure 11A–F); pharyngeal tooth relatively small, anteriorly located. Proventricle barrel shaped, also extending through 8 chaetigers, but about 1/3 longer than pharynx, with about 35 muscle cell rows. One of the specimens is a pre-epigamic female bearing eggs, with small notoaciculae and short notochaetae (Figure 12C).

Fig. 11.

Pionosyllis enigmatica (Wesenberg-Lund, Reference Wesenberg-Lund1950). (A) Anterior end, dorsal view; (B) anterior end, ventral view (A,B: holotype ZMUC-POL-16); (C) anterior end, dorsal view; (D) anterior end, ventral view (C,D: ZMUC-POL-17); (E) prostomium and everted pharynx; (F) everted pharynx, ventral view (E,F: IDENTICHAET). Scale: 0.56 mm.

Fig. 12.

Pionosyllis enigmatica (Wesenberg-Lund, Reference Wesenberg-Lund1950). (A) Anterior parapodium (ZMUC-POL-16) (dorsal cirrus and neurochaetae not drawn); (B) midbody parapodium, anterior view (dorsal cirrus not drawn); (C) midbody parapodium, posterior view, mature female (showing incipient notochaetae, neurochaetae not drawn) (B,C: IDENTICHAET); (D) posterior parapodium, anterior view (neurochaetae not drawn) (ZMH V-9771). Scale: (A) 0.13 mm; (B) 0.26 mm; (C) 0.14 mm; (D) 0.12 mm.

Fig. 13.

Pionosyllis enigmatica (Wesenberg-Lund, Reference Wesenberg-Lund1950). (A) Dorsalmost compound, elongate chaeta, posterior parapodium; (B) compound falcigers, posterior parapodium; (C) dorsal simple chaeta; (D) ventral simple chaeta (A–D: ZMH V-9771); (E) dorsalmost compound elongate chaeta, anterior parapodium; (F) dorsalmost compound falciger, same parapodium; (G) ventralmost compound falciger, same parapodium (E-G: IDENTICHAET). Scale: (A,B,E,F,G) 12 µm; (C,D) 20 µm.

Fig. 14.

Pionosyllis enigmatica (Wesenberg-Lund, Reference Wesenberg-Lund1950). (A–C) Dorsal, median and ventral falcigers, anterior parapodium (ZMUC-POL-16); (D,E) dorsal and ventral falcigers, posterior parapodium (IDENTICHAET); (F) anterior aciculae; (G) midbody aciculae (IDENTICHAET); (H) posterior aciculae (ZMH V-9771). Scale: (A–E) 12 µm; (F,H) 48 µm; (G) 37 µm.

REMARKS

Wesenberg-Lund (Reference Wesenberg-Lund1950) erected Hesiosyllis assuming the existence of five antennae, two of which fell off; however, the holotype now only has two lateral antennae and the base of the median one (Figure 7A). The specimen probably never had five antennae, as shown in Wesenberg-Lund (Reference Wesenberg-Lund1950: figure 18), but only four, the right antenna being doubled at its base, certainly an anomaly. Currently, only the lateralmost right lateral antennae is present, there is no evidence of the presence of a second antennae in the left side while the right side clearly shows the attachment of the missing antenna arising from the same ceratophore as the existing one. The median antenna is also missing. Furthermore, the two chitinous jaws found in addition to the single anterior tooth were absent either in the holotype or in any other specimen, likely being misinterpretation of folds on the pharynx wall.

Hesiosyllis was placed, with some reservations, within Syllidae (Wesenberg-Lund, Reference Wesenberg-Lund1950), then transferred to the Hesionidae (Fauchald, Reference Fauchald1977), but it is, in fact, clearly a synonymy of Pionosyllis (Drs M.E. Petersen, T.H. Perkins and P.R. Garwood, personal communication).

According to Petersen (personal communication) the ventral cirri of chaetigers 1–3 are noticeably smaller than the following ones, with those from chaetiger back having a slitlike pocket on the anteroventral side (Figure 8A,B), which is not visible on ventral cirri 1–3. These special ventral cirri might be related to reproductive, tube-building or some other function, but additional observations of specimens of both sexes and living material are required to assess the function of these structures (Petersen, personal communication).

TYPE LOCALITY

East of Iceland: 65°00′N 11°16′W (Station 59 ‘Ingolf’ expedition), 584 m.

DISTRIBUTION

East of Iceland, west coast of Sweden, North Sea. North-western Spain.

HABITAT

Ooze, mud; 90–584 m. On corals Madrepora oculata; 760–769 m depth.

Pionosyllis gigantea Moore, Reference Moore1908: 325, figures a–c; 1909: 326; Reference Moore1923: 256.- Hartman, Reference Hartman1969: 445, figures 1–3.- Banse & Hobson, Reference Banse and Hobson1974: 60 (key), figure 15f.

MATERIAL EXAMINED

North-eastern Pacific: vicinity of Naha Bay, Behm Canal, south-eastern Alaska, 75–245 m, gravel and sponges, coll. ‘Albatross’ dredgings, Station 4228, 1903 (holotype, USNM 5532); west of Gabriola, B.C., sponge bed, 6 July 1917 (1 spec., USNM 35633); Clallam Bay, Strait of Juan de Fuca, Washington, 193 m, gravel, 30 June 1938 (1 spec., USNM 33151); off the coast of southern California, coll. ‘Albatross’ dredgings, 1904 (2 spec., USNM 17363).

DESCRIPTION

Body long, thick, massive, dorsally curved, ventrally flattened, with well defined intersegmental furrows (Figure 15A,B), without colour markings (preserved specimens). The type is a poorly preserved, broken specimen, without antennae, tentacular or dorsal cirri, 11 mm long, 2.5 mm wide (anterior part with 33 chaetigers) plus a broken piece of 7 chaetigers, 4 mm long (40 segments, 16 mm long, 4 mm wide according to Moore, Reference Moore1908). Remaining specimens (non-type series) are also incomplete and fragmented. Prostomium subpentagonal, wider anteriorly and partially covered by first chaetiger; four lensed eyes in trapezoidal to square arrangement, anterior eyes slightly larger than posterior ones; antennae and tentacular cirri smooth; lateral antennae originating on anterior margin of prostomium, in front of anterior eyes, slightly longer than prostomium and palps together (Figure 15B); median antenna originating between posterior pair of eyes and ‘about 31/2 times…the length of the prostomium and palpi’ (Moore, Reference Moore1908); median antenna detached in all examined specimens; palps longer than prostomium, broad, large, divergent, fused at their bases and with a dorsal furrow (Figure 15B). Peristomium very short, almost completely hidden by first chaetiger (Figure 15B); tentacular cirri very similar in shape to antennae, ‘the dorsal about 5 times the length of the head and the ventral only about twice that length’ (Moore, Reference Moore1908); tentacular cirri detached or broken in all specimens. Dorsal cirri long, thin, slender, tapering towards the tip; anterior ones rugose to weakly wrinkled on distal part (Figure 15C), midbody and posterior dorsal cirri smooth, without articulations; dorsal cirri alternating long and short (Moore, Reference Moore1908). Ventral cirri of chaetigers 1 and 2 slender, those from chaetiger 3 similar in length but thicker, enlarged, ending bluntly on anterior parapodia (Figure 15A,C); from chaetiger 3 posteriorly becoming gradually smaller, thickened at base and distally pointed. Prechaetal parapodial lobes with a distal, rounded papilla dorsally (Figure 15B,C); anterior parapodia truncated distally, becoming tapered posteriorly. Compound chaetae heterogomph falcigers, with shafts slightly serrated subdistally (Figure 16A–D). Anterior parapodia with about 40–50 compound chaetae, decreasing in number to 16–18 posteriorly; blades of compound chaetae of anterior parapodia all similar in shape, bidentate, with distal tooth somewhat hooked and proximal tooth similar, with coarse and short spines, except distally, short and distally directed (Figure 16A); blades about 190 µm long dorsally, 100 µm long ventrally. Shape of the blades progressively changing posteriorly; posterior parapodia each with three different kinds of chaetae, dorsalmost one provided with elongate, slender blade with small, indistinct teeth (Figure 16B), some other dorsal chaetae with blade similar but shorter and wider, and provided with two short, rounded teeth (Figure 16C); remaining chaetae becoming shorter and much wider in ventral part of fascicle, with blunt, rounded teeth, and long and fine distal spines on cutting edge, making a tuft (Figure 16D). Blades of posterior chaetigers with sinuose furrow, apparently complete, on proximal tooth (Figure 16D), more marked in ventral part of fascicle. Blades of posterior chaetigers about 150 µm long dorsally, 60 µm ventrally. Anterior parapodia each with 5–6 aciculae, slightly curved at their end with an acute tip (Figure 16E); posterior parapodia each with 3 aciculae similar in shape to anterior ones. Simple chaetae not seen. Pharynx wide, massive, short, with a crown of ten short papillae surrounding opening; pharyngeal tooth rhomboidal, relatively small, anteriorly located (Figure 15A); inner surface of pharynx dark red, with a chitinous layer. Pharynx and proventricle not visible through body wall.

Fig. 15.

Pionosyllis gigantea Moore, Reference Moore1908. (A) Anterior end, ventral view with everted pharynx (USNM 33151); (B) anterior end, dorsal view (USNM 17363); (C) anterior parapodium (USNM 17363). Scale: (A) 0.56 mm; (B) 1.13 mm; (C) 0.26 mm.

Fig. 16.

Pionosyllis gigantea Moore, Reference Moore1908. (A) Compound chaetae, anterior parapodium; (B–D) dorsalmost, dorsal and ventral compound chaetae, posterior parapodium; (E) acicula (A–E: USNM 17363). Scale: 14 µm.

REMARKS

The posterior median cleft, forming two prostomial lobes, originally described (Moore, Reference Moore1908) have not been seen due to the poor condition of the specimens. Pionosyllis gigantea is characterized by its relatively large size (about 16 mm long), and the compound chaetae having blades with short, coarse, distally directed spines ending in tufts. It closely resembles P. enigmatica and P. kerguelensis, but differs mainly in the shape of compound chaetae. The furrow on the proximal tooth of blades of compound chaetae is only visible in several posteriormost chaetae, which were not described by Moore (Reference Moore1908) and Hartman (Reference Hartman1969).

TYPE LOCALITY

North-eastern Pacific: vicinity of Naha Bay, Behm Canal, south-eastern Alaska, 75–245 m.

DISTRIBUTION

South-eastern Alaska, western Canada, southern California.

HABITAT

Mud, volcanic sand, gravel, rocks and sponges; 75–398 m depth.

Eusyllis kerguelensis McIntosh, Reference McIntosh1885: 191, pl. 29, figure 4, pl. 33 figure 3, pl. 15a figure 13.- Ehlers, Reference Ehlers1897: 42; Reference Ehlers1913: 473.- Augener, Reference Augener1924: 376; Reference Augener1927: 152.- Monro, Reference Monro1930: 94, figure 30a–c; 1936: 130.- Knox, Reference Knox1951: 73; Reference Knox1960: 105.- Knox & Cameron, Reference Knox and Cameron1998: 49, figures 99–100.- Hartman, Reference Hartman1953: 20; Reference Hartman1964: 81, pl. 25 figures 2–3.- Wesenberg-Lund, Reference Wesenberg-Lund1961: 59, figure 19.- Hartmann-Schröder, Reference Hartmann-Schröder1965: 115, figures 74–75; 1986: 77.- Averincev, Reference Averincev1982: 19, pl. II, figures 1–2.- Hartmann-Schröder & Rosenfeldt, Reference Hartmann-Schröder and Rosenfeldt1988: 39, figure 16; 1990: 97; 1992: 98.

Pionosyllis comosa Gravier, Reference Gravier1906: 288.- Ehlers, Reference Ehlers1913: 473, pl.32 figures 1–4.- Benham, Reference Benham1927: 60.- Monro, Reference Monro1930: 92; Reference Monro1936: 128, figure 20.- Hartman, Reference Hartman1953: 23; Reference Hartman1964: 85, pl. 26 figures 7–8; Reference Hartman1967: 58.

Pionosyllis cosma [sic] Knox, Reference Knox1960: 106.- Knox & Cameron Reference Knox and Cameron1998: 51.

Pionosyllis kerguelensis San Martín & Parapar, Reference San Martín and Parapar1997: 291. San Martín & Hutchings, Reference San Martín and Hutchings2006: 337, figure 66A–F, 67A–L.

MATERIAL EXAMINED

Kerguelen: Station 149H, off Christmas Harbour, 200 m, coll. HMS ‘Challenger’, presented McIntosh (syntype of Eusyllis kerguelensis, BMNH 1885.12.1.142: 1 ant. end + 2 median parts); Falkland Islands (=Malvinas), Swedish Antarctic Expedition 1901–1903: 52°11′S 60°26′W, Port Albemarle, 40 m, sand with algae, 8 September 1902 (2 spec. of Pionosyllis comosa SMNH 3332, 3728); 53°45′S 61°10′W, Burwood Bank, 137–150 m, shell fragments and stones, 12 September 1902 (1 spec. of P. comosa SMNH 3660). Coast of northern Argentina: 37°15′S 56°8′W, 100 m, sand and gravel, 23 December 1901, Swedish Antarctic Expedition 1901–1903 (1 spec. of P. comosa SMNH 3826). South Georgia: 54°24′S 36°22′W, South Fjord in front of the Nordenskjöld glacier, 210 m, blue-grey mud with a few small stones, 29 May 1902, Swedish Antarctic Expedition 1901–1903 (1 spec., lot identified as Pionosyllis epipharynx SMNH 3033). Antarctic Expedition Charcot: 1910 (P. comosa MNHN A-76), 1906 (P. comosa). Crozert Island: Station 12, DC 12 (P. comosa MNHN A-921). Syntypes of P. comosa, MNHN 285, 286. South Shetland Islands, ‘Spanish cruise Bentart 94’, coll. ‘Hespérides’: Station 52, mixed sediment, 62°43′S 60°27′W, 84 m, 1 spec.; Station 71, rocks, 62°43′S 60°26′W, 50 m, 1 spec.; Station 77, mud and organic rests, 62°40′S 60°40′W, 130 m, 1 spec.; Station 92, rock and gravel, 62°40′S 60° 41′W, 34 m, 1 spec. Tasman, Station 2EBS, 42°17.99′S–170°00.00′E, 958 m depth, 1 spec. (SMF 13225).

REMARKS

Pionosyllis kerguelensis was originally included in Eusyllis without any reference to the incomplete crown of denticles on the edge of pharynx that characterize this genus. According McIntosh (Reference McIntosh1885), the pharynx has two crowns of papillae, in agreement with the examined specimen of the type series (besides its poor condition) and lacks pharyngeal denticles. Specimens from SMNH, identified as P. comosa, also appear to have two crowns of papillae.

Hartman (Reference Hartman1964) reported P. comosa as having chaetae with short, distally entire blades using Gravier's (1906) drawings, who described the species as having bidentate blades. This discrepancy is probably due to a mistake.

TYPE LOCALITY

Kerguelen Island, 200 m depth.

DISTRIBUTION

Coast of north Argentina, Antarctic and subantarctic seas: Kerguelen Island, South Georgia, Falkland Islands (=Malvinas), Magellan area, Davis Sea, Palmer Archipelago, Drake Passage, South Orkney Island, Antarctic Peninsula, South Shetland, Australia, New Zealand, Crozet Island.

HABITAT

Fine grey sandy mud, volcanic mud, hard bottom, sand and shells; intertidal to 2916 m (Ehlers, Reference Ehlers1913).

Pionosyllis magnifica Moore, Reference Moore1906: 223, pl. 10, figures 9–11; 1908: 325.- Hartman, Reference Hartman1969: 447, figures 1–3.- Kudenov & Harris, Reference Kudenov and Harris1995: 54, fig. 19.- López et al., Reference López, Britayev, Martín and San Martín2001: 400, figures 1–3.

Eusyllis magnifica Pettibone, Reference Pettibone1954: 261.

MATERIAL EXAMINED

Bering Sea, ‘Adler’ cruise 18; 150 m depth; 2 specimens (V.N. Goriachev leg.). Southern coast of Kamchatka peninsula, point Lopatka; 6–8 m depth, 1 specimen (A.A. Adrianov leg.).

TYPE LOCALITY

Admiral Inlet (Port Townsend, Washington), USA.

DISTRIBUTION

North Pacific from Alaska and north Japan to California.

HABITAT

Mud, pebbles–mud, sand and shells; in branchial chambers of giant crabs (López et al., Reference López, Britayev, Martín and San Martín2001); intertidal to 150 m depth.

Pionosyllis petalecirrus Averincev, Reference Averincev1982: 19, figures 3–6.

TYPE LOCALITY

Davis Sea, Antarctica.

DISTRIBUTION

Only known from the type locality.

HABITAT

Shallow water.

Pionosyllis stylifera Ehlers, Reference Ehlers1913: 474, pl. 31, figures 6–10.- Monro, Reference Monro1939: 111, figure 6.- Hartman, Reference Hartman1964: 88, pl. 27, figures 8&9.- Hartmann-Schröder & Rosenfeldt, Reference Hartmann-Schröder and Rosenfeldt1990: 97; Reference Hartmann-Schröder and Rosenfeldt1992: 98.- Knox & Cameron, Reference Knox and Cameron1998: 53.

MATERIAL EXAMINED

Kaiser Wilhelm II Land (Antarctica), Winterstation, syntypes (several specimens and fragments in dry condition), 31 July 1902; 22–24 November 1902; 11 November 1902, Ehlers coll., 385 m depth, Deutsche Südpolar Expedition 1901–1903; MNHUB (5808). Kaiser Wilhelm II Land (Antarctica), 1908, 385 m depth, 7 anterior, 2 posterior and 1 midbody fragments, ZMUH (PE-379; PE-380).

DESCRIPTION

Body long, thick, without colour markings, opaque, up to 15 mm long, 1 mm wide for about 60 chaetigers. Prostomium trapezoidal to pentagonal; four large eyes laterally placed on anterior half of prostomium, anterior pair slightly larger than posterior one. Palps broad, folded downwards, fused on their basal third, with a well defined furrow. Median antenna long and thick, cylindrical, originating between anterior pair of eyes; lateral antennae about 1/3 length of median one, similar in shape but slender, originating in front of anterior eyes. Peristomium dorsally reduced, covered by first chaetiger (Figure 17A). Buccal opening protected by 3–4 ventral lobes of peristomium (Figure 17B). Dorsal tentacular cirri long, similar in length to median antenna; ventral tentacular cirri somewhat shorter than half length of dorsal ones. Dorsal cirri of first chaetiger very long, reaching to chaetiger 8. Dorsal cirri of remaining anterior segments alternating in length, long ones slightly longer than body width, short ones shorter than half length of long cirri (Figure 17A), all thick at their bases, cylindrical, acute on distal end (Figure 17D); dorsal cirri of median and posterior segments all relatively short. Antennae, tentacular cirri and long dorsal cirri rough, giving a pseudoarticulated appearance, but not forming true articles; remaining dorsal cirri smooth or slightly rough. Intersegmental furrows well marked (Figure 17A). Parapodia relatively short and broad, with anterior and posterior parapodial lobes, posterior one longer than anterior lobe; ventral cirri short and broad, ovate (Figure 17D). Anterior parapodia each with about 13–18 compound chaetae, diminishing to 8–9 on posterior parapodia. Arrangement of compound chaetae inverse to that of most species of Syllidae, dorsal compound chaetae with shorter blades and ventral compound chaetae with longer blades (Figure 17D). Compound chaetae of most anterior parapodia each with bidentate blades provided with long distal tooth and short proximal tooth, distal tooth proportionally longer and more hooked ventrally (Figure 17E). On subsequent anterior chaetigers, dorsal compound chaetae with distal tooth rounded and proximal tooth fine and similar in length to distal tooth, also similar to spines of margin of blade; ventral compound chaetae with blades similar to dorsal chaetae of most anterior parapodia (Figure 17G). Compound chaetae of remaining parapodia with fairly wide blades, with distal tooth rounded and somewhat hooked, and with minute, nearly indistinct proximal tooth, with numerous short spines on margin (Figure 17I); blades of dorsal chaetae about 13–14 µm in length and those of ventral ones about 27 µm in length. Shafts of compound chaetae provided distally with numerous, short spines. Solitary dorsal simple chaeta from about chaetiger 18, slender, bayonet-shaped, ending in fine, unidentate tip (Figure 17H). Ventral simple chaetae not seen. Aciculae straight (Figure 17F), with tapering tip, 2 in each anterior parapodium, solitary in remaining parapodia. Pharynx and proventricle not clearly visible through body wall; pharynx extending through 5 segments, opening surrounded by a crown of 10 soft papillae; pharyngeal tooth large, located nearly on anterior margin of pharynx (Figure 17C). Proventricle rectangular, through about 4 segments, with about 7 muscle cell rows.

Fig. 17.

Pionosyllis stylifera (Ehlers, Reference Ehlers1913). (A) Anterior end, dorsal view (lacking lateral antennae, right dorsal tentacular cirrus and dorsal cirrus of first right parapodium); (B) anterior end, ventral view; (C) anterior end of pharynx; (D) midbody parapodium, anterior view; (E) dorsal, medium and ventral compound chaetae, anterior parapodium (1st parapodium); (F) acicula; (G) dorsal and ventral compound chaetae, anterior parapodium (5th chaetiger); (H) dorsal simple chaeta, medium parapodium (39th chaetiger); (I) dorsal, medium and ventral compound chaetae, posterior parapodium. Scale: (A,B) 0.14 mm; (C) 0.26 mm; (D) 0.13 mm; (E–I) 20 µm.

TYPE LOCALITY

McMurdo Sound, Antarctica.

DISTRIBUTION

New Zealand, subantarctic islands, Antarctic seas.

HABITAT

Muddy sand, with or without stones, fine sand, fouling; also hard bottoms and algae; from 4–500 m depth.

TYPE SPECIES

Pionosyllis lamelligera Saint-Joseph, 1886, by present designation.

DIAGNOSIS

Body long and slender with numerous segments, of medium size. Segments of midbody fused, forming single segments from groups of 2–3 chaetigers. Ciliary bands absent, sometimes rows of cilia on the parapodia. Prostomium provided with four eyes, sometimes also a pair of anterior eyespots, with three antennae and two palps. Median antenna inserted anteriorly, slightly back to the lateral antennae. Palps free to each other, divergent. Nuchal organs as two ciliated grooves. Two pairs of tentacular cirri. Antennae, tentacular cirri and dorsal cirri of chaetiger 1 long, weakly articulated; dorsal cirri of remaining chaetigers much shorter, smooth. Subcirral papilla absent. Ventral cirri inserted basally on parapodial lobes; ventral cirri of first chaetiger enlarged, foliaceous, laminar. Compound chaetae heterogomph falcigers with blades short to moderately long, bidentate; spines on margin short. Dorsal and ventral simple chaetae present on posterior parapodia. Tips of aciculae trifid. Parapodia without prechaetal lobes. Pharynx longer than proventricle. Pharyngeal tooth anteriorly located. Reproduction by epigamy (only demonstrated in the type species).

APOMORPHIES

Clade supported by one apomorphy: fused segments (character 8, state 1), state change is shared with Basidiosyllis sp. A. Palps free from each other (character 10) could be a reversal.

ETYMOLOGY

From Greek, Syn, fused, and Mero, parts, in reference to the fusing of two to three segments on midbody.

KEY TO SPECIES

1. 1. Posterior acicula neither enlarged nor protruding from parapodial lobes. Posterior compound chaetae including falcigers with moderately long, slender blades and falcigers with short blades, with proximal tooth longer than distal toothSynmerosyllis lamelligera

   • Posterior acicula enlarged, protruding from parapodial lobes. Blades of the compound chaetae similar all along the body2

2. 2. Blades of compound chaetae with dorsoventral gradation in sizeSynmerosyllis aciculata

   • Some compound chaetae with relatively elongated spiniger-like bladesSynmerosyllis yolandae.

Pionosyllis aciculata San Martín, Reference San Martín1990: 601, figures 8&9.

TYPE LOCALITY

Cayo Matías (Archipiélago de los Canarreos), southern Cuba.

DISTRIBUTION

Only reported from the type locality.

HABITAT

Algae, inside dead coral; 1–3 m depth.

Pionosyllis lamelligera Saint-Joseph, 1886: 163, pl. 8, figures 30–38.-Fauvel, Reference Fauvel1923: 288, figure 110a–g.- Cognetti, Reference Cognetti1957: 4142, figure 7.- Hartmann-Schröder, Reference Hartmann-Schröder1971: 154; Reference Hartmann-Schröder1996: 161.- Campoy, Reference Campoy1982: 340.- San Martín, Reference San Martín1984: 105, pls. 16, 17; 2003: 79, figures 30&31.

MATERIAL EXAMINED

MNHN A-76, 2 specimens; MNHN A-422, 3 specimens; MNHN A-371, 1 specimen belonging in fact to Eusyllis lamelligera; MNHN A-492, 1 specimen. Numerous specimens from all around the Iberian Peninsula.

TYPE LOCALITY

Roches-Bonnes (Dinard), France.

DISTRIBUTION

Atlantic coasts of Europe, from France to Cape Verde Islands, Mediterranean, Cuba.

HABITAT

Algae, kelps, among ascidians, Posidonia oceanica beds, calcareous concretions; intertidal to 40 m depth.

Pionosyllis yolandae San Martín & Hutchings, Reference San Martín and Hutchings2006: 348, figures 42C–F, 49A–C, 78A–J.

TYPE LOCALITY

Burrill Rocks, New South Wales (Australia).

DISTRIBUTION

Australia (New South Wales, Western Australia).

HABITAT

On gorgonaceans, ascidians, sponges and in sand, 14–244 m depth.

TYPE SPECIES

Eusyllis heterocirrata Hartmann-Schröder, Reference Hartmann-Schröder1959 by present designation.

DIAGNOSIS

Body small and slender, of meiofaunal size, with dorsolateral and ventrolateral rows of cilia. Segments not fused. Prostomium with eyes or without them, with three antennae and two palps. Median antenna inserted on posterior margin of prostomium. Palps fused at their bases, with a dorsal furrow, divergent, triangular in shape. Nuchal organs as two ciliated grooves. Two pairs of tentacular cirri. Antennae, tentacular cirri and dorsal cirri long, smooth, cylindrical; short, exogonid-like, small dorsal cirri present on some parapodia of midbody. Dorsal cirri absent on chaetiger 2. Subcirral papilla absent. Ventral cirri distally inserted on parapodial lobes. Compound chaetae homogomph, with bifid articulation, provided with short falcigers, slightly bidentate, with small proximal tooth; spines of blades short to moderate. Dorsal simple chaetae on posterior parapodia; apparently without ventral simple chaetae. Tips of aciculae distally rounded or laterally expanded. Parapodia with small prechaetal lobes. Pharynx longer than proventricle or similar in size. Pharyngeal tooth anteriorly located. Reproduction unknown.

APOMORPHIES

Clade supported by two apomorphies. The first one, the strong alternation in length of midbody dorsal cirri (character 21, state 1), is exclusive of the genus. The second one, the presence of some hemigomph or homogomph chaetae (character 44, state 1) is shared with Nereis pelagica, and with the species of Brevicirrosyllis, except B. gorringensis. Some other possible apomorphies can be considered. The ciliated lateral margins of prostomium (character 4, state 1), are shared with Nudisyllis tinihekea, Pionosyllis pulligera, Odontosyllis fulgurans and Eusyllis lamelligera. The ventral cirri originate distally on the parapodial lobes (character 25, state 1), and this state change is shared with Neopetitia amphophthalma and Dioplosyllis cirrosa. Finally, the aciculae have rounded tips (character 39, state 2), as in Exogone dispar, Brania pusilla and Perkinsyllis gen. nov.

ETYMOLOGY

The genus is named in honour of Dr Wilfried Westheide, who has made very important contributions to the knowledge of the family Syllidae and other interstitial polychaetes.

REMARKS

Eusyllis spirocirrata Hartmann-Schröder, Reference Hartmann-Schröder1959, clearly belongs to this genus. The holotype and paratype have been re-examined (HZMUH P-14587, P-14588), the later is a posterior part, probably of the former. The types are very small and covered with small crystals, so they are difficult to study. However, the species agrees quite well with W. heterocirrata, but is much smaller (juvenile specimen?) and has long spiralled cirri. As this difference is likely a fixation artefact, this species was not included in the analysis, as it was considered a synonymy of W. heterocirrata.

KEY TO SPECIES

1. 1. Without eyes (anterior eyespots present). Proventricle through about 1–2 segments, with 14 rows of muscle cellsWestheidesyllis corallicola

   • With two pairs of large eyes and a pair of anterior eyespots. Proventricle through about 3–4 segments2

2. 2. Blades of compound chaetae with similar, relatively coarse spines on margin. Ciliation of body not easily visibleWestheidesyllis heterocirrata

   • Blades of compound chaetae of anterior and midbody parapodia with long, fine spines on margin. Ciliation very marked on prostomium and ciliary bands on each segmentWestheidesyllis gesae

Pionosyllis corallicola Ding & Westheide, Reference Ding and Westheide1997: 285, figure 6a–j.

Pionosyllis corallicola San Martín & Hutchings, Reference San Martín and Hutchings2006: 328, figure 59A–E.

TYPE LOCALITY

Hainan Island, South China Sea.

DISTRIBUTION

Hainan. Western Australia.

HABITAT

Intertidal and subtidal coral sand.

Pionosyllis gesae Perkins, Reference Perkins1981: 1105, figure 10a–k.- Uebelacker, Reference Uebelacker, Uebelacker and Johnson1984: 30.69, figure 30.64.

TYPE LOCALITY

Hutchinson Island (Florida, USA).

DISTRIBUTION

Florida, Gulf of México, Cuba, Cape Verde Islands.

HABITAT

Interstitial on coarse and medium sand; algae.

Eusyllis heterocirrata Hartmann-Schröder, Reference Hartmann-Schröder1959: 118, figures 64–66.

Pionosyllis heterocirrata Hartmann-Schröder, Reference Hartmann-Schröder1992: 224–226, figures 11–15.

? Eusyllis spirocirrata Hartmann-Schröder, Reference Hartmann-Schröder1959: 121, figures 67–69.

TYPE LOCALITY

Pacific coast of El Salvador.

DISTRIBUTION

Circumtropical: Pacific Ocean (El Salvador), central Atlantic (Ascension Island), Indian Ocean (Tanzania, southern Africa).

HABITAT

Sediments in mangrove forests, fine to coarse sand, green algae.