Introduction
The genus Immersaria Rambold & Pietschm. was initially established as a monotypic genus for the lecideoid species I. athroocarpa (Ach.) Rambold & Pietschm. This taxon was previously placed in Lecidea [as L. athroocarpa (Ach.) Ach.], Amygdalaria [as A. athroocarpa (Ach.) Clauzade & Cl. Roux] and Porpidia [as P. athroocarpa (Ach.) Hertel & Rambold]. The following combination of morphological characters served to recognize the genus: a brown pigmented, areolate thallus with a distinct epinecral layer and an amyloid medulla, apothecia immersed in the thallus, with a dark, black or grey disc and a strongly reduced proper margin, during ontogeny frequently becoming separated by a fissure from the surrounding areole; Porpidia-type asci; and halonate, simple ascospores (Rambold Reference Rambold1989). Subsequently, five additional species were included, either transferred from Lecidea or Bellemerea (i.e. I. cupreoatra (Nyl.) Calatayud & Rambold, I. carbonoidea (J. W. Thomson) Esnault & Cl. Roux, and I. usbekica (Hertel) Barbero, Nav.-Ros. & Cl. Roux: Barbero et al. Reference Barbero, Navarro-Rosinés and Roux1990; Calatayud & Rambold Reference Calatayud and Rambold1998) or hitherto undescribed [Immersaria mehadiana Calat. & Rambold and I. olivacea Calat. & Rambold (Calatayud & Rambold Reference Calatayud and Rambold1998)]. The inclusion of these taxa entailed only a slight extension of the original genus concept of Rambold & Pietschmann (Rambold Reference Rambold1989): the ascoma discs may be brown, the ascospores are occasionally uniseptate or without a halo, and the pycnoconidia, usually bacillar, can be also pyriform or clavate.
In their phylogenetic studies on selected members of the Porpidiaceae and Lecideaceae, using the LSU region of the nrDNA and the β-tubulin fragment, Buschbom & Mueller (Reference Buschbom and Mueller2004) and Buschbom & Barker (Reference Buschbom and Barker2006) concluded that Porpidia is not monophyletic. In their phylogram Immersaria, represented by I. usbekica (not the generic type) appeared as sister to a clade with taxa currently placed in Lecidea and Cecidonia, but without support (Buschbom & Mueller Reference Buschbom and Mueller2004). In a separate analysis of LSU and β-tubulin Immersaria usbekica seemed more related to Porpidia but also without support (Buschbom & Barker Reference Buschbom and Barker2006). For an estimate of the generic status and precise phylogenetic position of Immersaria further species of the genus need to be included in phylogenetic analyses and additional markers used.
Materials and Methods
Material
The study is based on specimens collected between 2003 and 2008. Most were collected in NW Iran (East Azerbaijan), but single specimens were from Gilan, Kohgiluyeh o Boyer Ahmad, Mazandaran and Zanjan.
Morphological and chemical analyses
Morphology was studied under a stereomicroscope. Anatomy of the thallus and apothecia was studied on hand-cut sections mounted in water using a conventional high power light microscope. Amyloid reactions were tested using Lugol's solution with and without pre-application of KOH solution. TLC was performed according to Orange et al. (Reference Orange, James and White2001) using Merck silica gel 60 F254 pre-coated glass TLC plates and charring with 10% sulphuric acid for the visualization of the spots. The presence of 2′-O-methylsuperphyllinic acid was demonstrated by co-chromatography of a reference sample of Porpidia rugosa (Taylor) Coppins & Fryday (Arnold, Lich. Exs. 808, B).
The Species
Immersaria iranica Valadbeigi, Sipman & Rambold sp. nov
Thallus crustaceus, areolatus, fuscus ad rufofuscus, saxicola, prothallo nigro, areolis marginalibus radiantibus. Ascomata immersa, disco fusconigro, epruinoso, hymenio c. 160 µm alto, ascosporis subglobosis c. (5−)7·5−8–10(−14)×(5−)7·5−8–10(−14) µm. Conidiomata pycnidia, frequentia, apertura rimiformi, sinuosa ad stellata, conidiis clavatis vel raro bacilliformibus, c. 4×2 µm. Acidum 2′-O-methylsuperphyllinicum continens.
Typus: Iran, Mazandaran, Haraz road, 20 km to Aamol, 36°17′42″N, 52°21′40″E, on calcareous rock, 1475 m, 7 April 2006, T. Valadbeigi 9008 (TARI—holotypus; B, hb. Valadbeigi—isotypi).
(Fig. 1A & B)
Immersaria iranica. A, thallus areoles with ascomata (Sipman 55361); B, thallus areoles with stellate and winding, crack-like openings of pycnidia (Valadbeigi 9008). Scale = 0·5 mm.
Map showing the distribution of Immersaria athroocarpa (□), Immersaria cupreoatra (▲), Immersaria iranica (○), and Immersaria usbekica (●) in Iran.
Thallus crustose, areolate, up to several cm diam.; surface brown to slightly reddish brown, dull, smooth. Areoles flat to slightly convex, sometimes slightly undulate, occasionally with irregular grooves delimiting crystal-like warts, c. 0·5–1 mm diam., frequently with rounded, whitish rims, with blackish sides and usually sharp, sometimes rounded edges; marginal areoles larger and slightly radiating, c. 1 mm wide and 1·5 mm long. Hypothallus black to bluish black or whitish, frequently visible between the areoles. In section, thallus c. 0·3–0·5 mm thick; epinecral layer c. 15–25 µm high, I+ violet; (pheno-)cortical layer 30–37 µm thick, I+ violet with uppermost cells pale brown, hyaline below; medulla white, without crystals, I+ violet; photobiont chlorococcoid, cells globose, 5–13(−17) × 7·5–13 µm; medullary hyphae 2·5–3 µm thick.
Ascomata immersed, mostly one per areole, 0·3–0·5 mm diam., round or lobed (Fig. 1A), sometimes surrounded by a white rim, with crypto-lecanorine margin, occasionally separated from the areole by a fissure. Disc flat to slightly convex, black-brown, epruinose. Excipulum thin to absent, with an epinecral layer c. 12·5–15 µm high, laterally c. 10 µm thick. Hypothecium hyaline; photobiont cells present below the hymenium. Hymenium hyaline, c. 160 µm high. Paraphyses apically branched, occasionally anastomosing, c. 5 µm thick. Epihymenium brown, c. 12–25 µm high. Asci of Porpidia-type, clavate, c. 70–125(−130) × 30 µm. Ascospores 8 per ascus, (sub)globose, aseptate, halonate, non-amyloid, c. (5−)7·5−8–10(−14) × (5−)7·5−8–10(−14) µm.
Conidiomata (pycnidia) frequent on thalli bearing only few apothecia, opening by± stellate, winding cracks up to 0·5 mm long (Fig. 1B); conidia clavate to rarely bacilliform, simple, hyaline, c. 4 × 2 µm.
Chemistry. 2′-O-methylsuperphyllinic acid and traces of an unidentified substance, by TLC.
Etymology. The species epithet refers to its occurrence in Iran.
Distribution and habitat. Immersaria iranica occurs mainly in the north-west of Iran but extends to Mazandaran. We found it in five localities and thus it is probably the most common species of the genus in Iran. It grows on smooth faces of rock outcrops in sloping Astragalus steppe, on horizontal and inclined sides of more or less calcareous silicate rock, and it seems to prefer rather humid sites. The species was found once associated with I. cupreoatra.
Remarks. The new species fits perfectly into the current morphological concept of Immersaria. Immersaria iranica has a brown thallus with distinct epinecral layer, I+ violet medullary layer of the thallus, ascomata completely immersed in the thallus areoles, a thin to indistinct proper margin and Porpidia-type asci with non-amyloid ascospores. Strikingly, the conidia are clavate and pyriform. Such conidia are known within the genus Immersaria from I. olivacea Calat. & Rambold from Spain (Calatayud & Rambold Reference Calatayud and Rambold1998), but not from any other species currently included in the genera Porpida or Lecidea. Within the genus, I. iranica clearly differs from all hitherto known species by its pycnidia opening by stellate, winding cracks and by the presence of 2′-O-methylsuperphyllinic acid (Table 1), both characters hitherto being unique in the genus.
The major diagnostic characters and distribution data for Immersaria species in Iran
By its Iranian distribution the new species agrees with most Immersaria species which were all described from, and are restricted to the circum-Mediterranean and south-west Asian regions (Barbero et al. Reference Barbero, Navarro-Rosinés and Roux1990; Calatayud & Rambold Reference Calatayud and Rambold1998). The only exceptions are I. athroocarpa, which has a cosmopolitan distribution, and I. carbonoidea, which is known only from Alaska.
Specimens examined. Iran: East Azerbaijan: Shabestar district, W along road Tabriz-Marand, 7 km N of Sufiyan, 38°18′31″N, 45°57′69″E, 1450 m, 2007, H. Sipman, U. Søchting & M. R. Asef 55335 (B 60 0175446, IRAN); Jolfa district, 1 km S of Daran village, E of Hadi Shahr, 38°48′42″N, 45°49′09″E, 1700 m, 2007, H. Sipman, U. Søchting & M. R. Asef 55361 p.p. (B 60 0175471, IRAN); Arasbaran protected area, top mountain to Mazgar, 38°40′ N, 47°00′ E, 1800 m, 2008, T. Valadbeigi 9127 (hb. Valadbeigi). Mazandaran: Karaj-chalous road, Zangoole bridge, c. 2 km on the way from bridge, 36°21′ N, 51°45′ E, 2000 m, 2003, T. Valadbeigi 9046 (TARI, hb. Valadbeigi). Zanjan: Zanjan to Dandy, 5 km to Broon Gheshlagh village, near to Ghezel ozan river, 36°36′ N, 48°07′ E, 2096 m, 2006, T. Valadbeigi 9107 (TARI, hb. Valadbeigi).
Immersaria athroocarpa (Ach.) Rambold & Pietschm
in Rambold, Biblioth. Lichenol. 34: 240 (1989).
Lichen athroocarpus Ach., Lich. suec. prodr. (Linköping): 77 (1798)—Lecidea athroocarpa (Ach.) Ach., Method. Lich.: 41 (1803)—Porpidia athroocarpa (Ach.) Hertel & Rambold, in Hertel, Lecideaceae Exs., Fasc. VIII, nos 141–160: 8 (1985)—Amygdalaria athroocarpa (Ach.) Clauzade & Cl. Roux, Bull. Soc. bot. Centre-Ouest, Nouv. sér., num. spec. 7: 157 (1985); type: Sweden, [no date, locality or collector] (H-Ach—lectotype – Hertel Reference Llimona and Hladun1977).
For a description see Fletcher et al. (Reference Fletcher, Galloway, Coppins, Smith, Aptroot, Coppins, Fletcher, Gilbert, James and Wolseley2009).
Distribution. Cosmopolitan. In Iran it is known from a single collection only from Gilan where it occurred at low altitude on a calciferous outcrop in the Hyrcanian forest zone.
Specimen examined. Iran: Gilan: on the road to Javaherdasht, 37°00′ N, 50°18′ E, 700 m, 2003, T. Valadbeig 9022 (TARI, hb. Valadbeigi).
I. cupreoatra (Nyl.) Calatayud & Rambold
Lichenologist 30: 232 (1998).
Lecanora cupreoatra Nyl., Not. Sällsk. Fauna et Fl. Fenn. Förh. 8 (Lichenes Lapponiae orientalis): 181 (1866)—Aspicilia cupreoatra (Nyl.) Arn., Flora 53: 470 (1870).
For a description see Clauzade & Roux (Reference Clauzade and Roux1985).
Distribution. Mediterranean (Barbero et al. Reference Barbero, Navarro-Rosinés and Roux1990). In Iran known so far from two sites only in the north-west.
Specimens examined. Iran: East Azerbaijan: Jolfa district, 1 km S of Daran village, E of Hadi Shahr, 38°48′42″N, 45°49′09″E, 1700 m, 2007, H. Sipman, U. Søchting & M. R. Asef 55361 [B 60 0175471, IRAN]; Arasbaran protected area, top mountain to Mazgar, 38°40′ N, 47°00′ E, 1800 m, 2008, T. Valadbeigi 9988 (hb. Valadbeigi).
I. usbekica (Hertel) M. Barbero, Nav.-Ros. & Cl. Roux
Bull. Soc. Linn. de Provence 41: 140 (1990).
Lecidea usbekica Hertel, Khumbu Himal 6(3): 288 (1977)—for further synonyms see Barbero et al. (Reference Barbero, Navarro-Rosinés and Roux1990).
For a description see Esnault & Roux (Reference Esnault and Roux1987, sub Amygdalaria tellensis).
Distribution. Known from the western Mediterranean (Spain, Algeria) to Central Asia (Barbero et al. Reference Barbero, Navarro-Rosinés and Roux1990). Hertel (Reference Hertel2001) reported it for the first time from Iran. Our specimens are from the north-west and west of Iran (East Azerbaijan, Kohgiluyeh o Boyer Ahmad and Zanjan), while Hertel (Reference Hertel2001) reported it from Markazi province. The species probably has the widest ecological amplitude of any of the four Iranian species and may grow under the driest conditions. It was found in Quercus woodland (20 km from Semirom to Yassuj at 1750 m alt.) and in hilly steppe at higher elevations of 2470 m in Kohgiluyeh o Boyer Ahmad and 2800 m in Zanjan.
Specimens examined. Iran: Kohgiluyeh o Boyer Ahmad: c. 20 km from Semirom to Yassuj, 31°17′ N, 51°26′ E, 2470 m, 2003, A. A. Maassoumi & S. R. Safavi 2657 [B 60 0133417, TARI]; c. 71 km from Semirom to Yassuj, 31°09′ N, 51°14′ E, 1750 m, 2003, A. A. Maassoumi & S. R. Safavi 2670 (B 60 0133421, TARI). East Azerbaijan: Jolfa district, 1 km S of Daran village, E of Hadi Shahr, 38°48′42″N, 45°49′09″E, 1700 m, 2007, H. Sipman, U. Søchting & M. R. Asef 55363 (B 60 0175473, IRAN), 55368 (B 60 0175477, IRAN). Zanjan: Zanjan to Dandy, 5 km to Broon Gheshlagh village, near to Ghezel Ozan River, 36°36′ N, 48°07′ E, 2800 m, 2006, T. Valadbeigi 4067 (TARI, hb. Valadbeigi).
Key to the species of Immersaria in Iran
1 Apothecial disc black, more or less white-pruinose; epihymenium olivaceous grey or olivaceous brown; apothecial margin cryptolecanorine to lecideine; subhymenial algae absent; confluentic and/or gyrophoric acid present ... 2
Apothecial disc dark brown to black, epruinose; epihymenium brown; apothecial margin cryptolecanorine; subhymenial algae usually present; gyrophoric acid or 2′-O- methyl superphyllinic acid present ... 3
2(1) Thallus surface brown to yellowish brown, C− (confluentic acid); apothecial margin cryptolecideine, separated from thallus; hypothecium brown in lower part; ascospores 14–17 × 8–11 µm ... I. athroocarpa
Thallus surface olivaceous brown, C+ rose (gyrophoric and confluentic acids); apothecial margin cryptolecanorine, adnate to thallus; hypothecium colourless; ascospores 13–22 × 7–14 µm ... I. usbekica
3(1) Thallus brown, C+ rose (gyrophoric acid); conidiomata opening by simple, elongate pores; conidia bacilli form ... I. cupreoatra
Thallus brown to slightly reddish brown, C− (2′-O-methylsuperphyllinic acid); conidiomata opening by ± stellate, winding cracks; conidia mostly clavate to rarely bacilli form ... I. iranica
The major diagnostic characters and distribution of Immersia species in Iran is provided in Table 1.
Discussion
The detailed new information about the genus Immersaria in Iran presents an opportunity to re-evaluate the distribution patterns of the genus. The presence of four out of the seven known species of Immersaria in Iran implies a south-west Asian focus of distribution for the genus. The next diverse countries with three species each are Spain, with I. athroocarpa (Llimona & Hladun Reference Llimona and Hladun2001), I. olivacea Calatayud & Rambold (Calatayud & Rambold Reference Calatayud and Rambold1998) and I. usbekica (Barbero et al. Reference Barbero, Navarro-Rosinés and Roux1990), Italy with I. athroocarpa, I. cupreoatra and I. usbekica (ITALIC, http://dbiodbs.univ.trieste.it/global/chkpwforkeys) and Romania with I. athroocarpa, I. cupreoatra and I. mehadiana (Ciurchea in http://www.bgbm.org/BGBM/STAFF/Wiss/Sipman/Zschackia/Rumania/index.htm; Calatayud & Rambold Reference Calatayud and Rambold1998).
Within the genus two species groups are recognizable. One with black or white-pruinose ascocarp discs, with a wide or global distribution, including the species I. athroocarpa, I. carbonoidea, I. olivacea and I. usbekica; and a second group with dark brown, epruinose ascocarp discs, extending from SE Europe to Central Asia, including the species I. cupreoatra, I. iranica and I. mehadiana. This last group includes species with a more complex chemistry, such as I. mehadiana (Calatayud & Rambold Reference Calatayud and Rambold1998) and L. cupreoatra (unpublished data from Greece, in B). Further investigation of their chemistries and genotypic traits may lead to the recognition of additional species.
Dr M. Abbasi (Tehran), M. R. Asef (Tabriz), and Jasem Valadbeigi (Ilam) are gratefully acknowledged for assistance during fieldwork. The first author was financially supported by a grant from Shahid Beheshti University, Tehran, awarded to Dr H. Riahi.
