Sticta tunjensis Moncada & Lücking, 2012

Moncada, Bibiana & Lücking, Robert, 2012, Ten new species of Sticta and counting: Colombia as a hot spot for unrecognized diversification in a conspicuous macrolichen genus, Phytotaxa 74 (1), pp. 1-29 : 23-25

Sticta tunjensis Moncada & Lücking , spec. nov. ( Fig. 10 )

MycoBank #801852

Differing from Sticta weigelii by the flabellate lobes with distinctly maculate surface, the presence of marginal cilia, and the papillate cells of the basal membrane of the cyphellae.

Holotype: — COLOMBIA. Boyacá: Mun. Tunja, Vereda Barón Germania, El Malmo; 3065–3085 m; 17 Mar 2003, Alvaro et al. 474 ( UPTC; isotype: UDBC).

Primary photobiont cyanobacterial ( Nostoc ). Stipe absent. Thallus irregular, up to 5 cm diam., moderately branched, with 3–5 branches per 5 cm radius, branching pleurotomous; lobes flabellate, horizontal to subpendulous, imbricate, revolute to weakly canaliculate, their apices rounded to irregular in outline, involute, their margins crenate, not thickened; lobe internodes (3–)4–6(–8) mm long, (2–)3–8(–12) mm broad; thallus subcoriaceous, fragile. Upper surface smooth, dark green when fresh, pale ochraceous yellow to greenish grey in the herbarium, shiny; surface glabrous, without papillae and pruina, but with irregular, white to yellowish maculae; marginal cilia sparse or absent in oldest lobe portions, simple to fasciculate, white, up to 0.5 mm long. Apothecia not observed. Isidia abundant, predominantly marginal, aggregate, branched to coralloid, with long branches, horizontal to obliquely oriented, up to 0.5 mm long and 0.05 mm broad, blue-grey, matt, cylindrical; basal stalk when present cylindrical, without cyphellae. Lower surface smooth, cream-colored towards the apices and darker towards the center; primary tomentum irregular, absent towards the margin, thick, thinner towards the margin, fasciculate to spongy, soft, white to cream-colored; secondary tomentum pubescent, pale. Rhizines absent. Cyphellae 1–20 per cm 2 towards the thallus center and 41–60 per cm 2 towards the margin, scattered, rounded, urceolate with wide pore, erumpent to prominent, remaining below the level of the primary tomentum or emerging towards the margin, with the margin elevated and involute, white to cream-colored or dark brown towards the thallus center, without tomentum; pore (0.2–)0.3–0.5(–0.9) mm diam.; basal membrane pubescent, cream-colored, K + pale yellow, C –, KC–, P –. Medulla compact, white, K + pale yellow, C –, KC–, P –. No substances detected by TLC.

Upper cortex paraplectenchymatous, 12–25 µm thick, uniform, consisting of 2–3 cell layers with cells 3–8 µm diam., their walls 0.6–2.5 µ m thick and their lumina rounded to isodiametric, 1.5–5 µm diam. Photobiont layer 20–35 µm thick, its cells 10–18 µm diam. Medulla 45–55 µm thick, its hyphae 2.5 µm broad, without crystals. Lower cortex paraplectenchymatous, 12–15 µm thick, with 1–2 cell layers; cells 3–7 µm diam., their walls 0.6–1 µm thick. Hairs of lower primary tomentum 470–560 µm long, in fascicles of more than 20, unbranched hyphae, septate with free apices. Hairs of lower secondary tomentum 5–12 µm long, of single, unbranched hyphae, septate with free apices. Cyphellae cavity 50–220 µm deep; cells of the basal membrane with one papilla.

Distribution and Ecology: —South American Andes ( Colombia); found between 1900 and 3080 m altitude, in (sub-)andine forest of the Cordillera Oriental, in microhabitats with medium light intensity; growing on bark and soil and usually associated with liverworts of the genus Plagiochila .

Etymology: —Named after the type locality.

Remarks: — Sticta tunjensis shares the general morphology with S. weigelii in having branched, cyanobacterial thalli with marginal isidia ( McDonald et al. 2003; Galloway 2006). However, it can be distinguished by the green-grey rather than brown thallus color, the flabellate lobes, the distinctly maculate surface, the presence of marginal cilia, the paler lower tomentum, and the papillate cells of the basal membrane of the cyphellae. Phylogenetically, S. tunjensis is rather isolated and not closely related to any of the other species with S. weigelii morphology ( Moncada et al. 2012a).

Additional specimens examined (paratypes): — COLOMBIA. Boyacá: Mun. Villa de Leyva, SFF Iguaque ; 2100–2900 m; 9 Jun 2001, Linares et al. 9699 ( COL) . Santander: Mun. Charalá, Virolín, creek trail from Finca La Araña to Cascada ; 1950 m; 27 Apr 1984, Castro et al. 60 ( COL) .

Figures

FIGURE 10. Sticta tunjensis (holotype collection). A. Upper side of thallus. B. Lower side of thallus. C. Lower surface enlarged. D. Detail of lower surface. E–G. Detail of marginal isidia from upper and lower side. G. Young lobe tip showing cilia. H. Microscopic section through cyphella showing basal membrane with papillose cells. Scale in A–D = 5 mm, in E and F = 1 mm, in G = 0.5 mm, in H = 10 µm.