Coenogonium epiphyllum Vain., Ann. Acad. Sci. Fenn., Ser. A

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 : 110-111

Coenogonium epiphyllum Vain., Ann. Acad. Sci. Fenn., Ser. A , 15: 156 (1921b). ( Fig. 6D )

Dimerella pilifera Vězda , Nova Hedwigia 58: 128 (1994); Coenogonium piliferum (Vězda) Kalb & Lücking, Bot. Jahrb. Syst. 122 (1): 34 (2000).

Thallus basally crustose, densely or sparsely covered by erect algal cells which form a felt-like mat in part, foliicolous, continuous, thin, smooth, greyish green to olive-green, 15–50 mm diam., without a distinct corticiform layer, dull, prothallus absent. Photobiont Trentepohlia , cells angular to rounded, mostly in irregular plates, partly short threads, cells 10–20 × 4–10 μm. Apothecia epiphyllous, sessile on basal thallus and partly immersed in algal felt, rounded in outline, 0.4–0.8 mm diam., 150–200 μm high; disc plane, slightly concave in young apothecia, pale orange-yellow; margin thin, slightly prominent, later depressed, concolorous with the disc or slightly paler. Excipulum paraplectenchymatous with irregularly arranged cells, 55–70 μm broad, outer part I+ yellow-brown, inner part I–; cells globose to elongate, thin- or partly thick-walled, 1–10 × 2–5 μm. Hypothecium 15–30 μm high, colorless to pale yellowish. Hymenium 45– 50 μm high, colorless, I+ brown. Asci 40–45 × 5 (if spores oblique-uniseriate) –8 μm (if spores irregularly biseriate). Ascospores oblique-uniseriate or irregularly biseriate, narrowly ellipsoid, 1-septate, 5–7 × 1.8–2.5 μm, 2,7–3.9 times long as broad. Pycnidia not observed. Chemistry: no substances detected by TLC.

Distribution and habitat:—Paleotropics: Thailand, Philippines, Papua New Guinea, epiphyllous in tropical rainforests, mixed deciduous forests, dry evergreen forests and hill evergreen forests from 10–1375 m., thus showing a great ecological amplitude. C. epiphyllum is a new addition to the Thai lichen biota.

Remarks:— C. epiphyllum is closely related to C. queenslandicum , but is readily distinguished by its hairy thallus. Normally, the basal thallus is totally covered by the hairs growing out vertically. However, in a few cases, some parts of the thallus are smooth, without the characteristic hairs.

Material from Thailand examined:— Prachinburi Province: Nadee district ; Khao Yai National Park, near the station Bu Phram Nai ( Check Point 6), epiphyllous in a mixed deciduous forests, 185 m, 14°15’56.46’’ N, 101°51’09.33’’ E, 10 March 2000, K. Papong RU-17499 ( RAMK 004711 ) ; Saraburi Province: Muaklek district ; Khao Yai National Park, along trail from Heo Pla Kang waterfall ( Khao Fa Pha ) to Khao Nom Nang and Sun Sup Tai , epiphyllous in a dry evergreen forests, 1055 m, 14°31’03.30’’ N, 101°16’40.40’’ E, 28 June 2000, R. Boontavee RU-20494-4 ( RAMK 009174 ) ; Nakhon Ratchasima Province: Pakchong district ; Khao Yai National Park, along trail from visitor center to Gibbon study area, Mo Sing To , epiphyllous in a tropical rainforest, 830 m, 14°25’56.37’’ N, 101°22’14.36’’ E, 15 May 2001, K. Papong RU-21046, 21061 ( RAMK 009204 , RAMK 9196 ) ; Nakhon Ratchasima Province: Pakchong district ; Khao Yai National Park, hill evergreen forests E of main road 3077 to Khao Khiao site, 1375 m., 14°21’36.46’’ N, 101°23’46.83’’ E, 12 March 2000, K. Papong RU-18334-3, RU-18352-1 ( RAMK 009103 , RAMK 009100 ) ; Nakhon Ratchasima Province: Pakchong district, trail at km-stone 9 of Khao Rom site, near junction to Khao Khiao , 800 m, 14°19’29.31’’ N, 101°34’39.91’’ E, 04 April 1999, K. Papong RU-14051 ( RAMK 009043 ) .

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.