Introduction
Corticolous and/or lignicolous species of the lichen genus Caloplaca have been taxonomically well-treated by various workers across the world (e.g. Arup Reference Arup2006; Giralt et al. Reference Giralt, Nimis and Poelt1992; Hafellner & Poelt Reference Hafellner and Poelt1979; Hansen et al. Reference Hansen, Poelt and Søchting1987; Khodosovtsev et al. Reference Khodosovtsev, Kondratyuk, Makarova and Oxner2004; Laundon Reference Laundon, Purvis, Coppins, Hawksworth, James and Moore1992; Magnusson Reference Magnusson1944; Poelt & Hinteregger Reference Poelt and Hinteregger1993; Søchting Reference Søchting1989; Wade Reference Wade1965; Wetmore Reference Wetmore1994, Reference Wetmore2001, Reference Wetmore2004 a, Reference Wetmoreb, Reference Wetmore2007). For the Indian subcontinent, Awasthi (Reference Awasthi1991), Poelt & Hinteregger (Reference Poelt and Hinteregger1993) and Joshi & Upreti (Reference Joshi and Upreti2007, Reference Joshi and Upreti2008 a, Reference Joshi, Upreti and Satib) reported 11, 24 and 11 corticolous species of Caloplaca, respectively. While revising Teloschistacean taxa from India, one of the authors (YJ) reported 23 corticolous species of this genus from India (Joshi Reference Joshi2008c), one of which was collected 3 to 6 years ago in temperate regions of the Western Himalayas growing over dead wood. It is described here as new to science along with two new records to the Indian lichen flora. A revised and updated key of all the corticolous Indian epiphytic Caloplaca species is also provided.
Materials and Methods
The present study is based on collections in LWG (including LWU–AWAS). The morphological characters were examined on dry material under a dissecting microscope (×40). The thallus and ascomata were examined with a compound microscope (×100, oil immersion). The sections cut for studying anatomical details were mounted in water. For characters such as size of thallus, apothecium and thickness of the hymenium, 5 measurements were recorded from each specimen; 10 measurements per specimen were recorded for ascospore dimensions. The dimensions of epihymenium, hymenium and ascospores are generally presented as (minimum value recorded–) lowest specimen arithmetic mean observed—highest specimen arithmetic mean observed (–maximum value recorded). All measurements were made on material mounted in water, but the paraphyses were studied after replacing water with 25% KOH (Wetmore Reference Wetmore1994). Chemicals used in identification were 10% KOH (K), calcium hypochlorite (C), and para-phenylenediamine (PD). Secondary metabolites were identified by TLC as described by Walker & James (Reference Walker and James1980). The chromatograms were developed in solvent systems A (toluene: 1, 4-dioxane: acetic acid) and C (toluene: acetic acid). Terminology for tissues generally follows that of Nash & Gries (Reference Nash, Gries, Nash, Ryan, Gries and Bungartz2002) and Wetmore (Reference Wetmore1994).
The New Species
Caloplaca himalayana Y. Joshi & Upreti sp. nov
Caloplaca flavorubescens similis sed margine thallino deficienti, amphithecio sine algis, sporis parvis differt.
Typus: India, Himachal Pradesh, Shimla district, Rohru, Sungri, alt. 2600 m, on dead wood, 22 May 2002, S. Nayaka & R. Srivastava 02-219451 (LWG—holotypus; CAL—isotypus).
(Fig. 1)
Fig. 1. Caloplaca himalayana, habitus (holotype in LWG). Scale = 3 mm.
Thallus crustose, lignicolous, thin, continuous, determinate, irregular, 0·4–2(–3) cm diam., 25–30 μm thick, yellowish. Cortex thin, 8–13 μm thick, paraplectenchymatous, of thin- walled cells, algal layer even and continuous. Medulla macroscopically white, of loose hyaline hyphae, prosoplectenchymatous. Prothallus absent.
Apothecia biatorine, numerous, scattered to ± aggregated (1–4), sessile, round to ± angular owing to pressure, 0·2–1(–1·2) mm diam.; disc ferruginous red to reddish brown, plane to subconvex, glossy; proper margin smooth, entire, persistent, thin, 0·2–0·5 mm, flush, concolorous or paler than disc, glossy; thalline margin absent. Epihymenium golden brown, 15–30 μm thick; hymenium hyaline, 50–80 μm high; hypothecium hyaline, of isodiametric cells, with numerous oil-droplets; parathecium cupular, of thin walled elongated hyphal cells; amphithecium of thin-walled elongated hyphal cells, without algae or algae ± restricted to the base of parathecium. Paraphyses thin, simple, ± furcated at the tips, sometimes with ± inflated apices. Ascus 8-spored, ascospores polaribilocular, ellipsoid to broadly ellipsoid to ovoid, 9–11 × (4–)5–6(–7) μm, isthmus 2–4 μm.
Pycnidia not seen.
Chemistry. Thallus, apothecial disc and epihymenium K+ purple, C−, Pd−. Medulla K−, C−, Pd−. TLC: 7-chloroemodin (major) and parietinic acid (traces).
Ecology and distribution. Currently C. himalayana is known from two localities in Himachal Pradesh and one locality in Jammu & Kashmir. The species was found growing over dead wood between elevations of 2150–2800 m in temperate regions of the Western Himalayas. The three known communities in which the new taxon has been encountered, have a similar lichen composition (Lecanora and Rinodina spp.), along with a dense mat of cyanophycean species.
Remarks. The new taxon can be recognized by a thin, continuous yellowish thallus with ferruginous apothecia, absence of both a thalline margin and algae in the amphithecium, and lignicolous habitat. It is often confused with the citrine or orange-grey coloured species of C. herbidella (= C. herbidella f. citrinescens H. Magn.) which differs from the new taxa in being isidiate. Sometimes C. flavorubescens (Huds.) J. R. Laundon with deep reddish brown to brown apothecia is difficult to separate from the new taxon, but the former differs in the presence of a thalline margin, algae in the amphithecium and larger spores [12–20(–25) × 5–10(–13·6) μm]. Caloplaca ammiospila (Wahlenb.) H. Olivier, C. caesiorufella (Nyl.) Zahlbr., C. ferruginea (Huds.) Th. Fr., C. ferrugineofusca (Vain.) H. Magn., C. jenisejensis H. Magn., C. spitsbergensis H. Magn. and C. subathallina H. Magn., are other lignicolous or corticolous species having ferruginous or reddish brown coloured apothecial discs, but differ from the new taxon in having endoxylic, poorly to well-developed grey thalli and larger spores (12–17μm). On the other hand, C. asserigena (J. Lahm) Della Torre & Sarnth., having a ferruginous coloured apothecial disc and similar sized spores to that of the new taxon (9–12 × 5–6·5 μm), differs in its grey thallus and lecanorine to zeorine small apothecia (0·2–0·4 mm broad). Caloplaca juniperi Poelt & Hinter., another related species having a yellowish thallus and ferruginous coloured apothecial disc, differs from the new taxon in having squamulose thalli and pale yellow margined concave apothecia.
Additional specimens examined. India: Himachal Pradesh: Shimla district, Narkanda, 3–4 km towards Hatu Peak, alt. 2800 m, on dead wood, 2002, S. Nayaka & R. Srivastava 02-81522 (LWG). Jammu & Kashmir: Udhampur district, Patnitop, Tourist area, alt. 2150 m, on dead wood, 9 xii 2005, M. Sheikh s.n. (LWG).
New Records
Caloplaca alnetorum Giralt, Nimis & Poelt
Cryptog. Bryol. Lichénol. 13: 269 (1992).
This species is characterized by: irregular to ± orbicular, very thin (almost confused with the substratum) continuous to ± areolate, golden yellow thallus; orange apothecial discs; persistent proper margin; parathecium of ± elongated cells or paraplectenchymatous; amphithecium with algae; and spores with thickened end walls, 11–12 × 5–7 μm, with isthmus 4–6 μm. In external appearance the species is close to Caloplaca cerinelloides (Erichs.) Poelt, but differs in having a yellowish thallus and spores of variable shapes with thickened end-walls. Caloplaca cerinelloides has a greyish K− thallus. Caloplaca flavorubescens another related species, differs in having a greenish yellow thallus with a prominent thalline margin and larger broadly ellipsoid spores [12–20(–25) × 5–10(–13·6) μm].
Poelt (Reference Poelt1969, as “C. alnetorum ad int.”) and Giralt, Nimis & Poelt (Reference Giralt, Nimis and Poelt1992) reported this species from Europe and Nordic countries. Alon & Galun (Reference Alon and Galun1971) reported this species growing over bark of Quercus calliprinos and Pistacia palestina from Israel. It is a new record for India and is found growing on bark of Cedrus and Abies between elevations of 2000–2800 m in the Central Himalayas.
Additional specimens examined. India: Himachal Pradesh: Chamba district, Chamba, around Joth, alt. 2000–2350 m, on Cedrus bark, 2001, D. K. Upreti & S. Nayaka 01-75556 (LWG); Shimla district, Narkanda, 3–4 km towards Hatu Peak, alt. 2800 m, on Abies bark, 2002, S. Nayaka & R. Srivastava 02-67177 (LWG).
Caloplaca crocea (Kremp.) Hafellner & Poelt
J. Hattori Bot. Lab. 46: 19–24 (1979). – Lecidea crocea Kremp., Flora 59: 317 (1876).
The species is characterized by: a thin continuous to subareolate, smooth, whitish-grey, UV+ cream-yellow, K− thallus; yellow to yellowish orange apothecial disc; proper margin pale orange-brown; thalline margin persistent, smooth, thick, raised above the level of disc, concolorous with thallus; hypothecium paraplectenchymatous, with oil droplets; parathecium of radiating elongated hyphal cells, amphithecium with algae, outer surface with hyaline crystals, paraphyses simple to ± branched at the tips, spores trilocular, 16–18 × 8–10 μm, middle locule of similar size to the polar locules. In external morphology, the species is similar to C. aff. cerina (Ehrh. ex Hedw.) Th. Fr., a corticolous species, growing in temperate regions of India. However, the trilocular spores of C. crocea separate it from species of C. cerina group.
Hafellner & Poelt (Reference Hafellner and Poelt1979) reported C. crocea growing on bark and wood in Africa, Madagascar, Argentina, Brazil, Paraguay and Uruguay, while Wetmore (Reference Wetmore2007) reported it from North and Central America. It is a new record for India and is reported from the tropical regions of southern India, where it was found growing on trees at an altitude of 1100 m with C. bassiae (Willd. ex Ach.) Zahlbr.
Specimen examined. India: Tamil Nadu: Chennai, Pulmedu, Siruvani Hills, alt. 1100 m, on bark, 1996, G. N. Hariharan & Balaji CC9 (MSSRF).
Key to the epiphytic species of Caloplaca from the Indian subcontinent
A total of 32 species of epiphytic Caloplaca from the Indian subcontinent are keyed out, of which 23 occur in India (bold in key) and the remaining 9 are reported from other parts of the Indian subcontinent. Figures for spore measurements include (minimum value recorded–) lowest specimen arithmetic mean observed—highest specimen arithmetic mean observed (–maximum value recorded); dimensions given for apothecia all refer to their diameter. Vegetative propagules play an important role in demarcating the species, hence their presence or absence is an important distinguishing character. The number of locules within the spores varies between the species, but one type, polaribilocular is more common than than any other; the type of spore is only given when deviating from the normal type or where it is important for identification. The key in this paper will certainly not solve all problems, but should be consulted together with previous publications (cited above).
1 Thallus sorediate, isidiate or blastidiate ... ... 2
Thallus without soredia, isidia or blastidia ... 12
2(1) Thallus isidiate ... 3
Thallus sorediate or blastidiate ... 5
3(2) Thallus grey; apothecial disc ferruginous red ... ... C. herbidella (Nyl. ex Hue) H. Magn.
Thallus yellow; apothecial disc orange-brown to brownish red ... 4
4(3) Apothecia biatorine; cosmopolitan ... C. bassiae (Willd. ex Ach.) Zahlbr.
Apothecia lecanorine; restricted to temperate regions ... ... C. kashmirensis Joshi, Y. & Upreti
5(2) Thallus blastidiate ... C. farinosa Poelt & Hinter.
Thallus sorediate ... 6
6(5) Thallus leprose, completely sorediate or nearly so ... 7
Thallus only partly dissolved into soredia ... 9
7(6) Thallus completely leprose, golden to brownish yellow, consorediate ... ... C. chrysodeta (Vain. ex Räsänen) Dombr.
Thallus usually completely dissolved into soredia but not leprose ... 8
8(7) Soredia arising marginally ... C. phlogina (Ach.) Flagey
Soredia of medullary origin ... C. phloginopsis Poelt & Hinter.
9(6) Thallus grey ... 10
Thallus yellow-orange ... 11
10(9) Thallus distinctly grey, rarely sorediate, with numerous brown to blackish apothecia; tropical distribution ... C. atrosanguinea (G. Merr.) I. M. Lamb
Thallus grey, sometimes yellow tinged, distinctly sorediate, rarely apotheciate; temperate distribution ... C. granularis (Müll. Arg.) Zahlbr.
11(9) Soralia mainly marginal, disc yellowish orange ... C. flavocitrina (Nyl.) H. Olivier
Soralia of medullary origin, almost crater-like, disc ferruginous red ... ... C. chrysophthalma Degel.
12(1) Spores trilocular ... 13
Spores polaribilocular ... 17
13(12) Apothecial disc different shades of brown, K−; differs entirely from C. cerina ... 14
Apothecial disc yellow to orange to rust brown, K+ purple; often confused with C. cerina ... C. crocea (Kremp.) Hafellner & Poelt
14(13) Middle locule rhomboidal in shape ... C. brebissonii (Fée) Zahlbr.
Middle locule not rhomboidal ... 15
15(14) Anthraquinone and/or hyaline crystals absent in amphithecium and parathecium ... C. homologa Nyl.
Anthraquinone and/or hyaline crystals present in amphithecium and parathecium ... 16
16(15) Anthraquinone crystals present in epihymenium; hypothecium with oil droplets; middle locule of spores not elongated; thallus UV+ cream-yellow ... ... C. jatolensis Joshi, Y. & Upreti
Anthraquinone crystals absent in epihymenium; hypothecium without oil droplets; middle locule of spores elongated; thallus UV+ orange ... C. triloculans Zahlbr.
17(12) Thallus different shades of yellow to orange ... 18
Thallus different shades of grey ... 22
18(17) Apothecia ± stipitate; ascus 12–16 spored; thallus Xanthoriella-type (i.e. lobate species of Caloplaca resembling Xanthoria but devoid of lower cortex and rhizines) ... C. persica (Stein.) M. Stein. & Poelt
Apothecia sessile; ascus 8 spored; thallus not of Xanthoriella type ... 19
19(18) Thallus obligate on Juniperus bark or on dead wood; apothecial disc ferruginous red but never with orange tinge ... 20
Thallus not obligate over Juniperus bark or on dead wood; apothecial disc orange-yellow to brownish orange, rarely ferruginous red ... 21
20(19) Mature thalli squamulose; apothecia deeply concave in the beginning; spores 10–14 × 4·5–8 μm; obligate on Juniperus ... C. juniperi Poelt & Hinter.
Mature thalli continuous; apothecia plane from the beginning; spores 9–11 × 5–6 μm; obligate on dead wood ... C. himalayana Joshi, Y. & Upreti
21(19) Thallus greenish yellow to dull greyish, continuous to cracked areolate, prothallus black; hypothecium with oil droplets; spores ellipsoid with thin end walls ... ... C. flavorubescens (Huds.) J. R. Laundon
Thallus golden yellow, continuous to areolate, prothallus absent; hypothecium without oil droplets; spores ellipsoid with thickened end walls ... ... C. alnetorum Giralt, Nimis & Poelt
22(17) Apothecial disc different shades of brown to blackish ... 23
Apothecial disc yellow to orange or red ... 27
23(22) Spores > 20 μm long ... C. yuennana (Zahlbr.) Poelt & Hinter.
Spores shorter ... 24
24(23) Disc dark brown to black ... 25
Disc pale brown with some reddish or orange tinge ... 26
25(24) Epihymenium first K+ strong reddish purple then turning blue, thallus ± sorediate ... C. atrosanguinea (G. Merr.) I. M. Lamb
Epihymenium K+ purple not turning blue, thallus esorediate ... ... C. rinodinopsis Poelt & Hinter.
26(24) Thallus granular to verruculose, prothallus present (bluish grey); spores with thin end-walls ... C. haematites (Chaub.) Zwack
Thallus continuous to areolate, prothallus absent; spores with thick end-walls ... ... C. pollinii (A. Massal.) Jatta
27(22) Asci usually 12–16 spored; thallus indistinct ... C. cerinella (Nyl.) Flagey
Asci usually with 8 or fewer spores; thallus distinct ... 28
28(27) Margins whitish to dark bluish-grey, never yellow ... C. cerina (Hedw.) Th. Fr.
Margins usually yellow to orange at least in the upper part and around the disc, the flanks often discolouring, whitish or greyish ... 29
29(28) Spores with thick end-walls (hour glass type); parathecium distinctly paraplectenchymatous and cupulate ... C. cupulata Poelt & Hinter.
Spores not with thick end-walls; parathecium neither paraplectenchymatous nor cupulate ... 30
30(29) Thallus granulose ... 31
Thallus smooth or crustose-membranaceous ... 32
31(30) Prothallus absent, cortex of the amphithecium very thick; from Karakorum Range in Pakistan ... C. baltistanica Poelt & Hinter.
Prothallus distinct, pale grey with bluish tinge; from Europe & Israel ... ... C. haematites (Chaub. ex St.-Amans) Zwackh
32(30) Apothecia uniformly ferrugineous ... C. ferruginea (Huds.) Th. Fr.
Apothecia yellow to orange ... 33
33(32) Apothecia uniformly ceraceous yellow, but the thin, sharp margin often discoloured, becoming olivaceous or greyish black ... C. borealis (Vain.) Poelt
Apothecia yellow to orange, but margins usually not discoloured ... 34
34(33) Apothecia up to 1·5 mm in diam., distinctly zeorine, spores 14–22 × 7–11 μm ... ... C. satparae Poelt & Hinter.
Apothecia mostly 0·2–0·7(–1) mm in diam., ± indistinctly zeorine, spores smaller ... 35
35(34) Apothecia yellow to orange-yellow, margins somewhat brighter than discs; spores 9–13 × 5–7 μm ... C. cerinelloides (Erichsen) Poelt
Apothecia yellowish orange to orange or brownish orange, but flanks of the margins often becoming greyish; spores usually 11–14 × 5–7 μm ... ... C. pyracea (Ach.) Th. Fr.
We thank Dr R. K. Tuli, Director, National Botanical Research Institute, Lucknow, for providing laboratory facilities and to Dr S. Nayaka, Dr R. Srivastava and Mr Mukhtar Sheikh for collecting the specimens.
