Graphis koratensis Pitakpong, Kraichak & Lücking (2015: 338)

Kalb, Jutarat, Lücking, Robert & Kalb, Klaus, 2018, The lichen genera Allographa and Graphis (Ascomycota: Ostropales, Graphidaceae) in Thailand-eleven new species, forty-seven new records and a key to all one hundred and fifteen species so far recorded for the country, Phytotaxa 377 (1), pp. 448-450 : 448-450

Graphis koratensis Pitakpong, Kraichak & Lücking (2015: 338) .

Type:— THAILAND. Nakhon Ratchasima province: Sakaerat Environmental Research Station , on tree trunks in a dry dipterocarp forest, 380 m, 2014, Pitakpong D 205 (SUT!, holotype; F!, isotype) .

Thallus corticolous, pale whitish grey or grey-green, continuous, smooth to uneven, dull or slightly glossy. Lirellae erumpent to prominent with thick lateral to ± almost complete thalline margin, elongate, straight, curved or sinuous, sparsely branched, labia convergent, entire, appearing greyish black, whitish to gray-green pruinose along the slit, partly covered by a very thin thallus, disc closed, not visible from above, (caesiella- morph). Exciple laterally to completely carbonized; hymenium clear; ascospores 2–4 (–8)/ascus, hyaline, transversely 11–22-septate, 60–115 × 9–15 μm.

Chemistry: norstictic acid (major), subnorstictic acid (minor), connorstictic acid (minor) (anal. K. Kalb).

Distribution and habitat:—So far only known from northeastern Thailand where it is growing on bark in dry dipterocarp forests.

Remarks:—A similar species, also with a completely carbonized excipulum, large, transversely septate ascospores, and norstictic acid, is Allographa marginata (Raddi) Lücking & Kalb (see above), but that species differs in having strongly prominent lirellae with sharply delimited, black labia without pruina ( marginata -morph). The placement of G. koratensis in either Allographa or Graphis is unresolved ( Lücking & Kalb 2018). Phylogenetic analysis suggested placement in the Allographa clade ( Pitakpong et al. 2015), but this was caused by two mtSSU sequences which belong in the Phaeographis clade; Allographa is more closely related to Phaeographis than to Graphis and hence the mtSSU sequences pull the clade into Allographa if Phaeographis is not included in the analysis. In contrast, the nuLSU sequences of the same material belong in Graphis . A similar phenomenon is known from a few other instances in Graphis samples ( Lücking & Kalb 2018) and we currently have no explanation for this.

Material from Thailand examined:— Mukdahan province: Phu Pha Terb National Park , in a dry dipterocarp forest, 16°26’07”N, 104°48’21”E, 2014, Pitakpong A 04, 311 (SUT) .