Graphis omiana J. Kalb, Lücking & Kalb, 2018

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 omiana J. Kalb, Lücking & Kalb , sp. nov. Fig. 7A .

Mycobank MB 827644

Similar to Graphis luluensis A. W. Archer (2004: 326) , but differs in having larger and more septate ascospores (25–32 × 6–8 μm, 5–7- septate in G. luluensis ) usually less than 8/ascus and a more complex chemistry, but lacking norstictic acid, which is present in G. luluensis .

Type:— THAILAND. Ranong province, Suk Samran district, side road from Phetkasem Road ( Road #4) to Praphat Beach , area of Had Samran , on deciduous trees in a secondary forest along the beach, 2 m, 09°21’54’’ N, 98°23’46’’ E, 7 June 2015, J. Sutjaritturakan & K. Kalb 41208 ( RAMK, holotype, hb. K. Kalb 41539, 41566, isotypes) .

Etymology:—This new lichen species is named in honour of Assist. Prof. Dr. Wanaruk Saipunkaew, called Om, for her kind guidance during the PhD studies of the first author (J. K.).

Thallus corticolous, grey-green to light olive-green, up to 10 cm diam., 90–110 μm thick, continuous, corticate, prothallus indistinct, surface smooth to uneven due to clusters of crystals, glossy or dull. Thallus in section with distinct upper cortex, up to 20 μm high, with irregular algal layer up to 35 μm high, medulla filled with many clusters of crystals. Lirellae immersed to erumpent with thick, gently sloping thalline margin, very long and slender, curved or sinuous, irregularly branched, labia convergent, entire, black, not pruinose, disc closed, not visible from above, (leptogramma- morph). Exciple completely carbonized, laterally 90–110 μm wide, basally 100 μm high; hypothecium 10–20 μm high, ± hyaline; hymenium 110–130 μm high, inspersed (type A), epihymenium indistinct. Paraphyses unbranched; asci elongate claviform, ca. 100–120 × 15–20 μm. Ascospores (4–) 6 (–8)/ascus, hyaline, transversely 9–14-septate, 35–50 × 6–8 μm, I+ blue.

Chemistry: stictic acid (major), α- acetylconstictic acid (major), constictic acid (submajor to minor), neotricone (submajor to minor), peristictic acid (minor), hypostictic acid (minor) (anal. K. Kalb).

Distribution and habitat:—This new species is only known from the type locality where it is growing abundantly on deciduous trees along the beach.

Remarks:—Similar are Graphis luluensis (for differences see above) and also G. leptogramma . The latter shares the chemistry and the overall habitus, but is easily distinguished in having a laterally carbonized exciple and a clear hymenium.

Figures

FIGURE 7. A. Graphis omiana (scale = 0.5 mm); B. Graphis persicina (scale = 0.5 mm); C. Graphis pinicola (scale = 0.5 mm); D. Graphis plumierae (scale = 0.5 mm); E. Graphis prunicola (scale = 0.8 mm); F. Graphis schroederi (scale = 1 mm); G. Graphis subducta (scale = 0.6 mm); H. Graphis subhiascens (scale = 1.2 mm).