Heterodermia coralloidea Elix, Australas. Lichenol.

Mongkolsuk, Pachara, Meesim, Sanya, Poengsungnoen, Vasun, Buaruang, Kawinnat, Schumm, Felix & Kalb, Klaus, 2015, The lichen family Physciaceae in Thailand-II. Contributions to the genus Heterodermia sensu lato, Phytotaxa 235 (1), pp. 448-450 : 448-450

4. Heterodermia coralloidea Elix, Australas. Lichenol. 69: 12 (2011b) ( Fig. 6F )

Type :— AUSTRALIA. Australian Commonwealth Territory : Jervis Bay, Stony Creek, 34 km SE of Nowra, 2 m, 35°10' S, 150°45' E, on sandstone in dry sclerophyll forest beside creek with numerous shrubs and Livistonia, 8 November 1990, J. A. Elix 26421 (holotype CANB!) .

Thallus foliose, orbicular to irregularly spreading, loosely adnate, 2–7 cm wide. Lobes 0.7–1.5 mm wide, ± plane, sublinear-elongate, sympodially or irregularly branched, ± discrete to contiguous at the periphery, with short lateral lobes; apices not ascending, eciliate, phyllidiate. Upper surface whitish gray; phyllidia mostly marginal, more rarely laminal, dissected and erumpent, forming dense, coralloid pseudoisidia that cover most of the upper surface, rarely becoming granular. Medulla white. Lower surface with a pseudocortex, white to cream or pale tan near the centre. Lower surface rhizines rare, whitish to cream, concolorous with the thallus or becoming pale to dark brown towards the apices, simple to irregularly branched, marginal rhizines numerous, mostly simple, becoming irregularly branched with age, 0.3–1.0 mm long, ± projecting beyond the lobe margins. Apothecia and pycnidia not seen.

Chemistry: Cortex K+ yellow, C–, KC–, P+ yellow; medulla K+ yellow then red, C–, P+ dark yellow; containing atranorin (major), zeorin (major), 16β-acetoxyhopane-6α,22-diol (major), leucotylin (minor), 6αacetoxyhopane-16β,22-diol (trace), 6α-acetoxy-16β,22-dihydroxyhopane-25-oic acid (trace or absent), norstictic acid (major), connorstictic acid (trace).

Distribution and habitat:—Rare, known only from one collection on rock in a montane forest, also in Australia. While the only other collection originates from a dry coastal sclerophyll forest in Australia, the Thai specimen was collected at 1745 m above sea level; new to SE Asia and the Northern Hemisphere.

Remarks:—This lichen has a pale lower surface and marginal rhizines and marginal and laminal, phyllidiate isidia that erupt to form dense , coralloid pseudoisidia; the medulla contains norstictic acid, 16β-acetoxyhopane- 6α,22-diol and zeorin as major metabolites.

Material from Thailand examined:— Phitsanulok: Phu Hin Rongkla National Park, along the trail around the Phu Man Khaow , in montane forest, on rock, 1745 m, 16°54'23'' N, 101°05'38'' E, 31 March 2004, T . Deansa RU-TD 2, ( RAMK 21647 ) .

Figures

FIGURE 6. A. Polyblastidium hypoleucum, ascospores (mostly) without sporoblastidia (scale 10 µm). B. Polyblastidium magellanicum, Polyblastidia-type ascospores with one or more sporoblastidia (scale 10 µm). C. Heterodermia tropica, black conidiomata, immersed in the thallus or slightly emergent (scale 1 mm). D. Heterodermia angustiloba (scale 5mm). E. Heterodermia antillarum (scale 1 mm). F. Heterodermia coralloidea, holotype (scale 5 mm).