Cladonia flavocrispata 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 : 27-28

Cladonia flavocrispata Ahti & Sipman , sp. nov. ( Fig. 2 )

Mycobank # MB803521

Sicut Cladonia hians sed axillae non inflatae et acidum usnicum continens.

Type:— VENEZUELA. Bolívar: Cerro Guaiquinima , near NE edge of upper plateau, 05º54’N, 63º27’W, ca. 1250 m elev., rocky sandstone area with scrub on exposed ridge, 8 Febr. 1990, H. Sipman 26772 (holotype VEN!, isotypes B!, H!) .

Primary thallus evanescent, pale green, restricted to scattered, small squamules in the lower part of the podetia, ca. 0.2–0.5 × 1 mm, simple or somewhat split up irregularly into crenulate laciniae, esorediate. Podetia 5–12 cm tall, of indeterminate growth, pale greenish grey, in lower parts strongly variegated, with alternating pale greenish grey and brown to black patches, usually forming cushions composed of dense, erect, 1.0– 1.5 mm wide main stems; stereome soon brownish but not blackening inside; branching type anisotomous tricho- to polytomy; axils always perforated and only slightly swollen; branchlet tips short and darkbrown, usually under 0.5 mm long. Podetial surface matt, discontinuously very thinly corticate,with most of the stereome becoming bare with age, usually esquamose but some squamules may occur, particularly in fallen podetia; podetial squamules up to ca. 1.5 mm wide, divided in ca. 0.5 mm wide, elongate and crenulate lobes. Podetial wall 125–175(–200) µm thick, cortex 0–35 µ m; medulla mostly absent; stereome 125– 150 µm, pellucid, well-delimited. Conidiomata and hymenial discs not observed. Chemistry: thamnolic and usnic acids, sometimes with barbatic acid (TLC of 3 specimens). Colour reactions: P+ yellow, K+ yellow, KC+ yellow.

Distribution and ecology:— The available samples suggest that this is a Guayana Highlands endemic, known so far with certainty only from Venezuela. It is found in humid sandstone tableland, and it grows on sandstone flats with open bog vegetation between ca. (400–)1000 and 2500 m elev. From the Guianas only three doubtful collections are known, from the sandstone plateau of the Kaieteur Falls (see notes).

Additional specimens examined (paratypes): — VENEZUELA. Amazonas, Depto. Atabapo: Cerro Marahuaca, Cumbre , 2480–2580 m, 1982, M. Guariglia et al. 1512 (H!, VEN!) ; Bolívar: Chimantá, Toronotepui , 2100 m, 1985, Ahti et al. 45255 (H!, VEN!) ; Chimantá, 2130 m, Vareschi 9209 (H!, VEN!) ; Auyantepuí-Massif, Guayaraca , 1100 m, 1956, Vareschi & Foldats 6303 (H!, VEN!) ; Cerro Guaiquinima, 1000 m, 1990, Sipman 26514 (B!, H!, VEN!) ; id., 1500 m, 1990, Sipman 27101, 27105 (B, H, VEN) .

Remarks:— Cladonia flavocrispata is very similar to C. hians Ahti (2000: 284) and could be considered its usnic acid-strain. However, it is also larger in size. Like C. hians , it belongs in section Perviae, as demonstrated by the regular perforations of the axils. The species can be also easily confused with C. vareschii Ahti (1986: 218) . The latter has a more intense yellow tinge and its cortex is somewhat thicker. Its apical branchlets stand at an obtuse angle (>90°) and bend away from each other immediately. A very reliable difference is the (often scarce) presence of squamules in C. flavocrispata .

Three Guianas specimens ( GUYANA, Potaro-Siparuni Region, Kaieteur Falls National Park, around the airstrip, ca. 400 m elev., Sipman 40299, 40300, 40336 (B!, BRG!)) show a considerable resemblance, but deviate by the mostly closed axils not developing into funnels and the complete absence of squamules. In this repect they agree more with C. vareschii but lack the obtuse-angled apical branchlets and brownish colour. They may be more close to C. spinea Ahti (1986: 215) , which lacks main stems, however.

Figures

FIGURE 2. Cladonia flavocrispata. A. isotype (B); B. Guyana specimen of uncertain affinity (Sipman 40299 (B)). Bar = 2 cm.