Introduction
Tropical forests harbour high biodiversity, play a crucial role in the provision of key ecosystem services and are an important source of income at both national and local levels. Paleotropical areas within South and Southeast Asia are characterized not only by their high organismal diversity, but also by their high degree of endemism (Groombridge Reference Groombridge1992; Heaney Reference Heaney1993; Oliver & Heaney Reference Oliver and Heaney1996; Alcala & Custodio Reference Alcala and Custodio1997; Heaney & Mittermeier Reference Heaney, Mittermeier, Mittermeier, Gil and Mittermeier1997). Lichen diversity in the tropics is generally high, and some of the major groups of microlichens are chiefly tropical (Sipman & Harris Reference Sipman, Harris, Lieth and Werger1989; Aptroot Reference Aptroot2001; Lücking et al. Reference Lücking, Rivas Plata, Chaves, Umaña and Sipman2009). Recent surveys concentrating on Central and South America have unveiled a large number of new species and genera of microlichens. In contrast, the eastern paleotropics represent an extensive area with a major gap in lichenological knowledge, mainly regarding crustose microlichens. The largest family of tropical microlichens is Graphidaceae (which now includes Thelotremataceae), with approximately 50 genera and c. 1500 currently accepted species, a number which is expected to increase to 2000 (Mangold et al. Reference Mangold, Martín, Lücking and Lumbsch2008, Reference Mangold, Elix and Lumbsch2009; Lücking et al. Reference Lücking, Rivas Plata, Chaves, Umaña and Sipman2009; Rivas Plata et al. Reference Rivas Plata, Lücking, Sipman, Mangold, Kalb and Lumbsch2010).
Chapsa is one of the largest genera in the emended Graphidaceae, with over 70 species (Rivas Plata et al. Reference Rivas Plata, Lücking, Sipman, Mangold, Kalb and Lumbsch2010). Previously referred to as Asteristion Leight. or included in Thelotrema Ach. (Hale Reference Hale1981; Matsumoto Reference Matsumoto2000), the genus was resurrected by Frisch et al. (Reference Frisch, Kalb and Grube2006). Chapsa is characterized by being corticolous and having chroodiscoid ascomata; the proper exciple forms lateral paraphyses; the paraphyses are distinct and rigid with either moniliform or branched tips (occasionally simple); and the walls of the ascospores are often thickened (Salisbury Reference Salisbury1972; Hale Reference Hale1980, Reference Hale1981; Matsumoto Reference Matsumoto2000; Frisch et al. Reference Frisch, Kalb and Grube2006). The other two genera that show the same type of chroodiscoid ascoma morphology, Acanthotrema and Chroodiscus, differ from Chapsa by thin-walled ascospores and by having warty paraphysis tips (Acanthotrema), or being foliicolous and lacking lateral paraphyses (Chroodiscus). The genus Reimnitzia, which also has chroodiscoid ascomata, differs mainly in the absence of lateral paraphyses, a different ascus type and ascospore development, and the presence of columnar calcium oxalate crystals (Rivas Plata et al. Reference Rivas Plata, Lücking, Sipman, Mangold, Kalb and Lumbsch2010).
In the present paper, we describe three new species of Chapsa, all collected in tropical Asia.
Materials and Methods
Specimens were examined using Leica MS5, Motic K400, and Olympus SZX12 dissecting microscopes and Zeiss Axioscop 2, Olympus BH-2, and Vista Vision VWR V036 compound microscopes, in part connected to Jenoptic ProgRes C3 and C5 digital microscope cameras. Images were also made with Nikon Coolpix 5400 and Nikon Coolpix 8400 digital cameras. Specimens are deposited at F and PDA, with duplicates at BM. Anatomical measurements refer to specimens mounted in water; for iodine reactions, we used Fluka 62650 Lugol solution. We employed thin-layer chromatography (TLC) using solvent C (Lumbsch Reference Lumbsch, Kranner, Beckett and Varma2002).
Results
Chapsa mastersonii Rivas Plata, Lumbsch & Lücking sp. nov.
MycoBank No.: MB564107
Sicut Chapsa recurva sed ascosporis longioribus differt.
Typus: Philippines, Nueva Vizcaya (Luzon), Mt. Palali, near Solano, 16°26′N, 121°13′E, 1400 m, montane rain forest, on lower stem in semi-exposed situation, March 2007, Rivas Plata & Lücking 1111G (F—holotypus).
(Fig. 1)
Chapsa mastersonii. A–D, thallus with apothecia. [A & B Rivas Plata 1111G (F); C, Rivas Plata 1077A (F); D, Rivas Plata 1076 (F)]. In colour online.
Thallus corticolous, up to 5 cm diam., 60–120 µm thick, continuous, endoperidermal; surface uneven to shallowly verrucose, grey; in section with dense, paraplectenchymatous cortex and irregular algal layer with clusters of calcium oxalate crystals.
Apothecia erumpent, angular-rounded, 1·0–3·5 mm diam.; disc exposed, covered by thick, white pruina; proper margin indistinct, fused or sometimes free in upper part; thalline margin lobulate, with 4–7 conspicuous, erect to recurved lobules covered with white pruina along inner margin. Columella absent. Excipulum indistinctly paraplectenchymatous, 100–150 µm thick, orange-brown; lateral paraphyses present. Hymenium 120–160 µm high, clear; paraphyses unbranched. Ascospores 1–2(–4) per ascus, richly muriform, 90–130×17–25 µm, oblong and often slightly curved, with rather thin septa and rectangular lumina, colourless, I−.
Chemistry. Stictic acid (major) and satellite substances.
Etymology. This new species is dedicated to Patrick Masterson (Chicago) for his interest in the Botany Department of The Field Museum (Chicago).
Ecology and distribution. Chapsa mastersonii has been found in the (lower) montane rain forest of Mt. Palali between 1000 and 1400 m. It typically grows on small stems and on branches and twigs in shaded to semi-exposed situations, the large and conspicuous apothecia then contrasting with the comparatively small thallus.
Notes. The new species is characterized by rather large apothecia with the disc covered by a thick, white pruina, large, muriform ascospores, and a stictic acid chemistry. It is most closely related to C. recurva (G. Salisb.) Frisch, which was also described from the Philippines and agrees in most features except that the ascospores are much shorter (30–60 µm) (Frisch et al. Reference Frisch, Kalb and Grube2006). Chapsa lordhowensis Mangold and C. zahlbruckneri (Redinger) Frisch agree in the muriform ascospores and stictic acid chemistry but have more irregular, fissurinoid-chroodiscoid apothecia with more or less erect lobules (Frisch et al. Reference Frisch, Kalb and Grube2006; Mangold et al. Reference Mangold, Elix and Lumbsch2009); C. lordhowensis also differs in the broader, amyloid ascospores, whereas in C. zahlbruckneri the ascospores are both shorter and broader. Chapsa eitenii (Hale) Frisch and C. patens (Nyl.) Frisch are also superficially similar but both lack a thallus cortex, and C. eitenii produces protocetraric acid whereas C. patens lacks lichen substances (Frisch et al. Reference Frisch, Kalb and Grube2006; Rivas Plata et al. Reference Rivas Plata, Lücking, Sipman, Mangold, Kalb and Lumbsch2010); in both species the ascospores are also broader.
Additional specimens examined. Philippines: Nueva Vizcaya (Luzon): Mt. Palali, near Solano, 16°26′N, 121°13′E, 1400 m, montane rain forest, on liana in shaded situation, 2007, Rivas Plata & Lücking 1076 (F); ibid., 1000 m, (lower) montane rain forest, on lower stem in shaded situation, 2007, Rivas Plata & Lücking 1077A (F); ibid., 1400 m, montane rain forest, on branch in shaded situation, 2007, Rivas Plata & Lücking 1139 (F); ibid., 1400 m, montane rain forest, on branch in shaded situation, 2007, Rivas Plata & Lücking 1200 (F).
Chapsa wijeyaratniana Weerakoon, Lumbsch & Lücking sp. nov.
MycoBank No.: MB564108
Sicut Chapsa alstrupii sed thallo sorediato et ascosporis septis et parietibus tenuibus differt.
Typus: Sri Lanka, Central Province, Knuckles Conservation area, Dotalugala mountain, 3·5 km SWS of Hunnasgiriya, 7°20′N, 80°51′E, 1310 m, submontane forest, on bark of Symplocos cochinchinensis, September 2008, Weerakoon & Wijeyaratne 742 (PDA—holotypus; BM, F—isotypi).
(Fig. 2)
Chapsa wijeyaratniana. A–D, thallus with apothecia. [A & B, Weerakoon 1025 (PDA); C & D, Weerakoon 742 (F)]. In colour online.
Thallus corticolous, up to 10 cm diam., 50–100 µm thick, continuous, endoperidermal; surface smooth to uneven, appearing finely grainy (periderm cells), olive-grey to olive-brown, abundantly sorediate; in section ecorticate, with irregular algal layer largely immersed in periderm, with a few scattered clusters of calcium oxalate crystals. Soralia maculiform to capitate, 0·3–1·0 mm diam., white, farinose.
Apothecia erumpent, angular-rounded to rarely lobate or aggregate, 1·0–2·0 mm diam.; disc exposed, flesh-coloured where visible but usually covered by thick, white pruina; proper margin indistinct, fused; thalline margin lobulate to recurved with 5–10 small, erect to recurved lobules covered with white pruina along inner margin. Columella absent. Excipulum paraplectenchymatous, 50–70 µm thick, colourless; lateral paraphyses present. Hymenium 80–120 µm high, clear; paraphyses unbranched. Ascospores 8 per ascus, submuriform with 3–5 transverse septa and 0–2 longitudinal septa per segment, 15–25×6–8 µm, oblong, with rather thin septa and rectangular lumina, colourless, I−.
Chemistry. No substances detected by TLC.
Etymology. This new species is named in honour of Professor Chandrani Wijeyaratna, Chair of Botany of the University of Sri Jayawardenepura, Sri Lanka, and pioneer lichenologist in the country, who initiated lichen studies in the early nineties. She has collected lichens from various parts of Sri Lanka, and the collection includes several new species and many new records.
Ecology and distribution. The new species was collected in submontane forest on the bark of Symplocos cochinchinensis in the Knuckles mountain range. Another collection was made in March 2010 on a Calophyllum sp. from Hulankanda Trail of the Kalupahana Mountains. The species appears to prefer shady moist conditions and smooth bark.
Discussion. Chapsa wijeyaratniana is only the fourth species in the genus to produce genuine soralia. Two other recently described species, C. defectosorediata Lücking (Sipman et al. Reference Sipman, Lücking, Aptroot, Chaves, Kalb and Umaña2012) and C. thallotrema Lücking & N. Salazar (Lumbsch et al. Reference Lumbsch, Ahti, Altermann, Amo de Paz, Aptroot, Arup, Bárcenas Peña, Bawingan, Benatti and Betancourt2011), differ in having olive-green, epiperidermal thalli with a dense cortex and large, transversely septate, amyloid ascospores. Chapsa sorediata Kalb can also be distinguished by transversely septate, amyloid ascospores which are, however, smaller than in the two preceding species (Kalb Reference Kalb2009); in addition, its thallus lacks a distinct cortex but is epiperidermal. Apart from the soralia, Chapsa wijeyaratniana is similar to C. alstrupii Frisch and C. sipmanii Frisch & Kalb in having large apothecia and small, muriform ascospores, but those taxa have epiperidermal, corticate thalli and ascospores with a distinct endospore and rounded lumina (Frisch et al. Reference Frisch, Kalb and Grube2006). Chapsa hiata (Hale) Sipman (Sipman et al. Reference Sipman, Lücking, Aptroot, Chaves, Kalb and Umaña2012) and C. kalbii Frisch are two other species with small, muriform ascospores which, like the new species, have ecorticate thalli (Frisch et al. Reference Frisch, Kalb and Grube2006); both lack soralia. Chapsa kalbii differs also in the weakly amyloid ascospores having a well-developed endospore and rounded lumina, whereas the ascospores in C. hiata are very small (12–15 µm long).
Additional specimen examined. Sri Lanka: Central Province: Kalupahana, Ranamure, 7°27′N, 80°48′E, 1240 m, mossy montane cloud forest, 2010, Weerakoon & Wijeyaratne 1025 (PDA).
Chapsa wolseleyana Weerakoon, Lumbsch & Lücking sp. nov.
MycoBank No.: MB564109
Sicut Chapsa rubropulveracea sed thallo corticato differt.
Typus: Sri Lanka, Central Province, Knuckles Conservation area, Kalupahana Mountain along the Lebannan watta, Rathnagiriya-Kalupahana, 16 km WNW of Hettipola, 7°25′N, 80°46′E, 1280 m, mossy mountain forest, growing on twigs of Calophyllum trapezifolium, April 2009, Weerakoon & Wijeyaratne 1043 (PDA—holotypus; BM, F—isotypi).
(Fig. 3)
Chapsa wolseleyana. A–D, thallus with apothecia. [A–D Weerakoon 1043 (F)]. In colour online.
Thallus corticolous, up to 8 cm diam., 50–100 µm thick, continuous; surface uneven, white-grey to grey-green; in section with loose, irregular upper cortex, irregular algal layer and indistinct medulla with clusters of calcium oxalate crystals.
Apothecia erumpent, rounded to lobate, 0·5–1·0 mm diam.; disc exposed, flesh-coloured where visible but usually covered by thick, red to purplish red or mottled white-red pruina; proper margin indistinct; thalline margin lobulate to recurved with 4–6 erect to recurved lobules covered with white pruina along inner margin. Columella absent. Excipulum paraplectenchymatous, 30–60 µm thick, colourless or infused with red pigment; lateral paraphyses present. Hymenium 200–225 µm high, clear, epihymenium with layer of red granules, K+ dissolving into a yellow-green cloud; paraphyses unbranched. Ascospores 1 per ascus, richly muriform, oblong-ellipsoid, 120–150×30–35 µm, with rather thin septa and rectangular to slightly rounded lumina, colourless to pale olive-brown, I−.
Chemistry. No substances detected by TLC but apothecial disc with pigment dissolving and producing K+ yellow-green efflux, suggesting presence of isohypocrelline (Mathey et al. Reference Mathey, van Roy, van Vaeck, Eckhardt and Steglich1994).
Etymology. This new species is dedicated to Pat Wolseley, lichenologist at the Natural History Museum in London, in honour of her invaluable contributions to lichenological studies in Sri Lanka for more than a decade by conducting workshops, supervising post-graduate students and assisting in several lichen projects carried out in the country.
Ecology and distribution. The new species was collected in the Knuckles Mountains, in mossy montane forests located in the central region of Sri Lanka, growing on twigs of Calophyllum trapezifolium. The new species is rare and known only from the type locality. It was found on twigs of trees that were exposed to high light intensity and winds.
Notes. This new species is distinguished by its pigmented disc and muriform ascospores that become olive-brown. Only a few species of Chapsa have pigmented discs: C. magnifica (Berk. & Broome) Rivas Plata & Mangold with orange, C. waasii (Hale) Sipman & Lücking with pink-purple, C. rubropulveracea Hale ex Mangold et al. with red-purple, C. rubropruinosa Messuti & Codesal with red-brown, and C. neei (Hale) Mangold & Lücking with purple-brown pigment (Messuti et al. Reference Messuti, Codesal, Mangold, Lücking and Lumbsch2010; Rivas Plata et al. Reference Rivas Plata, Lücking, Sipman, Mangold, Kalb and Lumbsch2010; Lumbsch et al. Reference Lumbsch, Ahti, Altermann, Amo de Paz, Aptroot, Arup, Bárcenas Peña, Bawingan, Benatti and Betancourt2011). All have small, transversely septate ascospores (brown in C. neei). Chapsa rubropulveracea is otherwise morphologically most similar to the new species, but lacks a cortex and its thallus is farinose. The only other known species of Chapsa with large, muriform, grey-brown ascospores is C. stellata (Hale) Sipman, which has an olive-green to yellowish thallus with dense cortex and grey-pruinose apothecial discs.
The research work carried out in Sri Lanka was supported by a research grant from the University of Sri Jayawardenepura, Sri Lanka, Research Grant No. ASP/06/Re/2008/11. A travel grant from the British Lichen Society enabled the first author to work on the material at the Natural History Museum, London. Fieldwork in the Philippines was funded by the NSF project “Phylogeny and Taxonomy of Ostropalean Fungi, with Emphasis on the Lichen-forming Thelotremataceae” (DEB 0516116 to The Field Museum; PI: HTL; Co-PI: RL). This publication continues our world-wide and community-wide revision of Graphidaceae in the frame of the NSF-funded project “ATM – Assembling a taxonomic monograph: The lichen family Graphidaceae” (DEB-1025861 to The Field Museum; PI: HTL, CoPI: RL).
