Caloplaca decipioides Arup
Mycobank MB 517744
Thallus to 1.5 cm, single or coalescing with other thalli, lobate, growing radiately in rosettes with marginal lobes and the centre covered by smaller, irregularly arranged, often imbricate lobes; lobes 0.5–2.3 × 0.2–0.6 mm, slightly convex to rather flat, slightly wider toward tips, irregularly branched one to three times, divided by narrow but distinct furrows, 0.1–0.2 mm wide, surface ± smooth to finely granular near lobe tips, yellow (in shade) to dark orange or red-orange, slightly paler at margin and partly with very thin white pruina; soralia ± punctiform or irregular in outline, laminal or terminal on central lobes, initiating as globose to elongate isidia that soon dissolve into soredia; isidia 75–125 µm when globose and up to 200 µm long when elongate, in dense clusters, of the same color as the thallus; soredia 35–60 µm, rather compact with rather smooth surface, yellow to orange-yellow, contrasting against the darker thallus; cortex 20–40 µm thick, paraplectenchymatous with thin-walled cells 4–8 µm in diameter, without epinecral layer; algal layer ± continuous with trebouxioid algal cells 7–12 µm in diameter; prothallus not seen; pycnidia not seen. Apothecia not seen. Secondary chemistry (HPLC): Parietin (major), fallacinal (major), vicanicin (major, isofulgidin (major), teloschistin (major) and traces of emodin, parietinic acid and caloploicin. This chemosyndrome corresponds rather well with A+3 according to Søchting & Frödén (2002).
The species of Caloplaca presented in this paper was collected in South Korea by G. Thor who kindly put the material at the author's disposal. The lobate species turned out to be difficult to determine using appropriate keys and works. Neither Gaya's recent work on the C. saxicola group (Gaya, 2009) nor those from North America (Arup, 1995; Wetmore & Kärnefelt, 1998; Wetmore, 2007), nor Kondratyuk's papers on Australian species (Kondratyuk et al., 2007a, 2007b, 2009a, 2009b), nor Poelt & Hinteregger's (1993) book on Himalayan Caloplaca helped in determining the species. None of the older papers from Asia were useful either (Nylander, 1890; Magnusson, 1940; 1944). Finally, the new species failed to match any of the many genetically investigated species of Caloplaca in the possesion of the author and U. Søchting or in Genbank. The new species is characterized by the orange lobate thallus with clusters of isidia that dissolve into soredia. It is similar to C. decipiens (Arnold) Blomb. & Forssell, a rather common lichens on anthropogenic calcareous substrates in Europe, but differs in the flatter lobes and in the soredia that develop from breakdown of globose isidia. In addition, the isidia and soralia are laminal or terminal on horizontal lobes rather than borne on ascending lobe tips as in C. decipiens. Finally, C. decipioides differs in its ecology as it grows on hard, non-calcareous rocks and not on limestone, concrete or mortar. C. decipens sometimes produces apothecia, but the new species has not yet been found fertile. Molecular data also show that these two species are not closely related, as C. decipiens belongs to the C. saxicola group (Gaya et al. 2008) and C. decipioides belongs to another clade within the family (unpublished data). The new species could also be confused with C. cirrochora (Ach.) Th. Fr., but differs from that species in the same way as it differs from C. decipiens.
The epithet refers to the similarity with C. decipiens.
The new species was collected under an overhang of a tall rock with a river running below. The rock face was exposed to the south and there were no trees giving any shady. The lichen flora is very rich at the locality and C. decipioides was very abundant in suitable places away from both rain and running water. The rock was very hard and probably of some kind of greenstone, but did not contain any lime. The new species is so far known only from the type locality. The locailty is situated in the Sorak-san National Park and many habitats included mainly oldgrowth forests on steep mountain slopes dominated by deciduous trees. The climate is somewhat continental with warm summers (up to 36°C) and cold winters (down to –17°C). The annual precipitation is 1300 mm and the mountains are snow-covered from November to April. The species was collected at just above 400 m altitude. The distribution range is not yet known for this species but it is probaly rare since the collector has not seen it elsewhere in Korea or Japan on his exursions in the region.
Type:—SOUTH KOREA: Gangwon Province: Inje-gun, Buk-myun, Yongdae-ri, Sorak-san National Park, inner part of the massif Sorak Mts, along the road in Backdam Valley from Backdam (Paekdam) temple towards the village Yongdae-ri, where the road crosses the river ca. 1.5 km NW Backdam (Paekdam) temple; 38°10’N, 128°22’E, 410–420 m; on almost vertical rock, shaded from running water, probably at least partly with a higher pH than true siliceous rocks, exposed to S at the river; Oct 2006, Thor 20768 (holotype UPS; isotypes NIBR, UPS).
Additional specimens examined (paratypes):—None.
Caloplacae decipienti similis, sed lobi magis plani, soralia ex isidiis demum fractis formata, nec in calce crescit.