Coenogonium frederici (Kalb) Kalb & Lücking

Kalb, Jutarat, Boonpragob, Kansri & Kalb, Klaus, 2016, New Coenogonium species (Ostropales: Coenogoniaceae) from Thailand, new reports and a revised key to the species occurring in the country, Phytotaxa 283 (2), pp. 101-122 : 111-112

Coenogonium frederici (Kalb) Kalb & Lücking , Fungal Diversity 23: 297 (2006). ( Fig. 6E )

Dimerella frederici Kalb, Folia Geobot. Phytotax. 15: 310 (1980).

Thallus crustose, corticolous, continuous, ± thick, dull, smooth, grey to greyish green, 15–40 mm diam., with a distinct, 10–20 μm thick corticiform, paraplectenchymatic layer; prothallus absent. Photobiont Trentepohlia , cells angular to rounded, mostly in irregular, compact clumps, cells 8–12 × 7–10 μm. Apothecia sessile, rounded in outline, 0.4–0.6 mm diam., 170–200 μm high; disc plane or slightly convex with age, concave in young apothecia, pale orange to ochre; margin initially prominent, then depressed, smooth (in most Thai specimens) or slightly denticulate (in type), cream-colored. Excipulum paraplectenchymatous with irregularly arranged cells, 60–75 μm broad, outer part I+ yellow-brown, inner part I–; cells globose to elongate, thin- or partly thick-walled, 8–12 × 4–7 μm. Hypothecium 15–20 μm high, colorless to pale yellowish. Hymenium 70–90 μm high, colorless, I+ blue, then quickly reddish brown then greyish brown. Asci 60–75 × 6 (if spores oblique-uniseriate) –10 μm (if spores irregularly biseriate). Ascospores oblique-uniseriate or irregularly biseriate, broadly ellipsoid, 1-septate, 8–12 × 3–4 μm, 2,2–3.1 times long as broad. Pycnidia wart-shaped, 0.12–0.15 mm diam., whitish. Conidia bacillar, non-septate ca. 3 × 1 μm. Chemistry: no substances detected by TLC.

Distribution and habitat:— U.S.A. Hawaii (type), BRITISH OVERSEAS TERRITORY. Bermuda, leg. Berger 22369 (herb. Berger, unpublished). In Thailand, this species occurs in hill evergreen forests from 1800–2185 m. Coenogonium frederici is a new addition to the Thai lichen biota.

Remarks:—This species is very similar to C. convexum and C. nepalense . It can be distinguished from both by its broadly ellipsoid ascospores (3.5–5.8 times long as broad in C. convexum and 3.2–5.1 times long as broad in C. nepalense ). It is furthermore similar to C. portoricense Mercado-Díaz & Lücking , but differs from that species by the different color of the dics and the thallus (disc bright orange, thallus shiny with a white-grey prothallus in C. portoricense ).

Material from Thailand examined:— Chiang Mai Province: Doi Inthanon National Park, Nature trail Kew Mae Pan , in hill evergreen forests, 2185 m, 18°33’27.06’’ N, 83°33’27.06’’ E, 10 January 2007, M. Sanglarbcharoenkit RU-SMCH14, RU-SMCH19 ( RAMK 015470 , RAMK 01573 ) ; ibid., 17 March 2007, V. Chaiyabutr, RU-VC2 ( RAMK 027815) ; ibid., Fhang district ; Doi Pha Hom Pok National Park , in hill evergreen forests, 1800 m, 23 January 2005, S. Jariangprasert ( MU, Chiang Mai 5829) .

Figures

FIGURE 6. Habitus photographs of Coenogonium species. A. Coenogonium convexum (KK 41133), scale 1 mm. B. Coenogonium coronatum (KK 41136), scale 0.5 mm, scale of inlet 0.15 mm. C. Coenogonium dilucidum (KJ 41439), scale 0.25 mm. D. Coenogonium epiphyllum (RAMK 009100), scale 0.25 mm. E. Coenogonium frederici (Isotype, KK 41445), scale 0.5 mm. F. Coenogonium geralense (KK 41446), scale 1 mm.