Graphis oxyclada Müller Arg. (1885: 512)

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 oxyclada Müller Arg. (1885: 512) .

Type:— KENYA. Taïta hills [in monte Nidi], ramulicola, Hildebrand 2540, ( G!, holotype) .

Fig. 6G .

Thallus corticolous, whitish or whitish gray, continuous, smooth, scarcely corticate, dull or slightly glossy. Lirellae prominent, with a thick lateral thalline margin, elongate, up to 6 mm long, straight, curved or sinuous, irregularly branched, labia convergent, entire, disc concealed, partly slightly open, whitish pruinose (marginata- or rarely farinulenta- morph). Exciple completely carbonized; hymenium clear; ascospores 8/ascus, hyaline, with 11–13 transverse septa, 36–56 × 8–9 μm; 30–45 × 5–7 μm ( Lücking et al. 2008, holtype); 32–45 × 7–8 μm (protologue).

Chemistry: no lichen substances by TLC (anal. J. Sutjaritturakan).

Distribution and habitat:—pantropical, reported from Florida ( Lücking et al. 2011) , Africa (type locality), the Philippines ( Aptroot & Sparrius 2008 –present) and here from Thailand for the first time. It was collected in South Thailand from bark of a teak tree in a plantation at 170 m.

Remarks:— Graphis oxyclada is well distinguished in having mostly marginata -morph lirellae, a completely carbonized exciple, a clear hymenium, medium-sized ascospores and producing no secondary lichen substances. Similar is G. immersicans (see above), but this species has erumpent lirellae and slightly smaller ascospores with less septa (7–9-septate, 28–32 × 7–9 μm).

Material from Thailand examined:— Phuket province: Thalang district, in the area of Kho Tosae , in a teak plantation ( Tectona grandis ), 170 m, 07°53’58’’ N, 98°23’57’’ E, 24 April 2012, J. Sutjaritturakan 4112, (hb. K. & J. Kalb 42420) .

Figures

FIGURE 6. A. Graphis kelungana (scale = 0.5 mm); B. Graphis khaojoneana (scale = 0.4 mm); C. Graphis litoralis (scale = 0.5 mm); D. Graphis modesta (scale = 0.5); E. Graphis myrtacea (scale = 0.5); F. Graphis negrosina (scale = 0.5 mm); G. Graphis oxyclada (scale = 0.8 mm); H. Graphis paralleloides (scale = 0.3).