Coenogonium queenslandicum (Kalb & Vězda) Lücking, Lücking et al.

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 : 118

Coenogonium queenslandicum (Kalb & Vězda) Lücking, Lücking et al. , Lichenologist 33: 201 (2001). ( Fig. 8C )

Dimerella queenslandica Kalb & Vězda, In : Vězda & Kalb, Nova Hedwigia 53: 218 (1991).

Thallus crustose, foliicolous, continuous, thin, smooth, dull, light yellowish green to greenish grey, 10–30 mm diam., without a distinct corticiform layer; prothallus absent. Photobiont Trentepohlia , cells angular to rounded, mostly in irregular plates, partly short threads, cells 10–20 × 5–7 μm. Apothecia rarely epiphyllous, usually marginally hypophyllous, sessile with a distinctly constricted base, rounded, 0.4–0.8 mm diam., 125–175 μm high; disc plane, concave in young apothecia, pale yellow to yellowish ochre; margin thin, smooth, concolorous with disc or cream colored. Excipulum paraplectenchymatous with irregularly arranged cells, 80–100 μm broad, outer part I+ yellow-brown, inner part I–; cells globose to elongate, thin- or partly thick-walled, 5–10 × 4–7 μm. Hypothecium 10–12 μm high, colorless to pale yellowish. Hymenium 40–50 μm high, colorless, I+ blue, then quickly reddish brown. Asci 45–55 × 6–7 μm. Ascospores irregularly biseriate, narrowly ellipsoid, 1-septate, 6–8 × 1.5–2.1 μm, 3.8–4.7 times as long as broad. Pycnidia common, applanately wart-shaped, 0.12–0.25 mm diam., yellowish green. Conidia ellipsoid, non-septate 3 × 1.7–2 μm. Chemistry: no substances detected by TLC.

Distribution and habitat:—Occurs in Australia and Thailand on leaves of various trees and shrubs in hill evergreen forests, tropical rain forests and dry evergreen forests from 420–1375 m. C. queenslandicum is a new addition to the Thai lichen biota.

Remarks:— Coenogonium fallaciosum (Müll. Arg.) Kalb & Lücking is similar in having an epiphyllous thallus and marginally hypophyllous apothecia and at the type locality of C. queenslandicum ( AUSTRALIA. Queensland: Lamington National Park, surroundings of O’Reillys Guesthouse), the two species co-occur on the same trees. They can be readily distinguished (even in the field) because the apothecia of C. fallaciosum are more than double the size (up to almost 2 mm) of the apothecia of C. queenslandicum . In addition, C. fallaciosum differs in having broadly ellipsoid ascospores, 6–9 × 2.5–4 μm, 1.5–3.0 times long as broad and the conidia are 3.5–4 × 1.2–2 μm.

Material from Thailand examined:— Nakhon Ratchasima Province: Pakchong district ; Khao Yai National Park, in a 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-18351, 18359-1 ( RAMK 009101 , RAMK 009104 ) ; ibid. tropical rainforest along Pha Kluay Mai nature trail to Heo Suwat waterfall, 775 m, 14°25’57.22’’ N, 101°24’26.40’’ E, 12 March 2000, K. Papong RU-18289 ( RAMK 009094 ) ; Saraburi Province: Muaklek district ; Khao Yai National Park, in a dry evergreen forests along trail from Heo Pla Kang waterfall ( Khao Fa Pha ) to Khao Nom Nang and Sun Sup Tai , epiphyllous, 1055 m, 14°31’03.30’’ N, 101°16’40.40’’ E, 28 June 2000, K. Papong RU-20525, 20529 ( RAMK 009192 , RAMK 009193 ) .

Figures

FIGURE 8. Habitus photographs of Coenogonium species. A. Coenogonium nepalense (KK 35180), scale 1 mm. B. Coenogonium pineti (KK 38905), scale 0.3 mm. C. Coenogonium queenslandicum (KK 41131), scale 0.5 mm. D. Coenogonium subborinquense (KK 38820) thallus with apothecia and pycnidia (arrow), scale 1 mm. E. Coenogonium subluteum (KK 39803), scale 0.5 mm. F. Coenogonium verrucimarginatum (KJ 41288), scale 0.25 mm.