Cladonia rupununii Ahti & Sipman, 2013

Ahti, Teuvo & Sipman, Harrie J. M., 2013, Ten new species of Cladonia (Cladoniaceae, Lichenized Fungi) from the Guianas and Venezuela, South America, Phytotaxa 93 (1), pp. 25-39 : 35-36

Cladonia rupununii Ahti & Sipman , sp. nov. ( Fig. 8)

Mycobank # MB 803525

Sicut Cladonia macilenta , sed podetia regulariter ramosa, in parte applanata, toto sorediosa; disci hymeniales coccinei; acidum didymicum et acidum barbaticum continens.

Type:— GUYANA. Upper Takutu Distr. : southern Rupununi savanna, Kusad Mt., SE side, 2°47'N, 59°51'W, 450 m elev., forest along stream in upper part of valley, on Curatella trunk, 29 Sept. 1992, H . Sipman 57749 (holotype B!, isotype BRG!) .

Primary thallus persistent, consisting of very small, 0.5–2 mm long, dissected squamules, veined below; often slightly sorediate along margins. Podetia up to 2 cm tall, 0.3–1 mm thick, of determinate growth, very slender, whitish grey, dichotomously or digitately branched, especially in upper parts; branchlets divergent; axils closed; tips bluntish; ascyphose. Podetial surface abundantly farinose-sorediate throughout. Podetial wall anatomy not studied. Hymenial discs red, not seen in maturity. Conidiomata born on basal squamules or at tips of podetia, ampullaceous, black, containing purple slime. Chemistry: didymic, barbatic, trace of demethylbarbatic acids. Colour reactions: P –, K –, KC–.

Distribution and ecology:— A Guyana endemic, so far as known, collected once in a forest island on a hilltop in the Rupununi savanna in SW Guyana, on rotten log in clearing along a stream, at 450 m elev.

Additional specimens examined:— known from the type only.

Remarks:— Very similar and apparently closely related to Cladonia macilenta Hoffmann (1796: 126) , but more branched. Also similar to Cladonia prancei , which is much more robust, forms narrow scyphi, and always contains thamnolic acid. Chemically, it is similar to C. didyma (Fée 1825: 118, 101) Vainio (1887: 137), but that species has smooth, pellucid podetia producing granules or squamules and lacks soredia.