Cora squamiformis Wilk, Lücking & Yánez-Ayabaca, 2013

Lücking, Robert, Dal-Forno, Manuela, Lawrey, James D., Bungartz, Frank, Holgado Rojas, María E., Hernández, Jesús E., Marcelli, Marcelo P., Moncada, Bibiana, Morales, Eduardo A., Nelsen, Matthew P., Paz, Elias, Salcedo, Luis, Spielmann, Adriano A., Wilk, Karina, Will-Wolf, Susan & Yánez-Ayabaca, Alba, 2013, Ten new species of lichenized Basidiomycota in the genera Dictyonema and Cora (Agaricales: Hygrophoraceae), with a key to all accepted genera and species in the Dictyonema clade, Phytotaxa 139 (1), pp. 1-38 : 16-18

Cora squamiformis Wilk, Lücking & Yánez-Ayabaca , sp. nov. ( Fig. 8 )

Mycobank #805382

Genbank ITS barcoding sequence: KF443240

Differing from the morphologically similar Cora bovei in the smaller lobes with plane surface, and from the closely related C. pavonia in the much smaller, often irregularly bent lobes giving the thallus a squamulose appearance.

Holotype: — BOLIVIA. La Paz: Franz Tamayo, Madidi National Park , Sanchez Pass between Pelechuco and Keara; 14° 43' S, 69° 08' W, 4677 m; high mountain vegetation, on ground between mosses; 13 October 2007, Wilk 7577 ( KRAM; isotypes: F, LPB).

Thallus on soil between bryophytes, macrosquamulose, up to 3 cm across, composed of 3–5(–10) semicircular lobes per thallus; lobes 0.5– 1 cm wide and 0.5– 1 cm long, unbranched or sparsely branched, olive-grey to grey with indistinct color zonation when fresh, with thickened, involute, white margins, darker grey to brownish-grey in the herbarium; lobes ascending and typically with much bent, sinous margins ('salad'-like). Upper surface glabrous but appearing rough; involute margin with underside finely arachnoid; lower surface ecorticate, arachnoid (representing the exposed medulla), white when fresh and becoming greywhite in the herbarium. Thallus in section 200–300 µm thick, with upper cortex, photobiont layer, and medulla; upper cortex much reduced, formed by a 20–50 µm thick layer of loosely woven, irregularly arranged, 4–6 µm thick hyphae and a 15–25 µm thick layer of strongly compacted, periclinal hyphae 3–5 µm thick and with brownish color, 'medullary' layer absent; photobiont layer 50–100 µm thick, irregular, composed of clusters of short, coiled cyanobacterial filaments wrapped in a dense, paraplectenchymatous hyphal sheath formed by jigsaw puzzle-shaped cells, clusters 30–50 µm diam., individual photobiont cells 9– 13 µm broad and 5–6 µm long, green to yellow-orange in upper portions, penetrated by tubular fungal hyphae; heterocytes sparse, hyaline to pale yellow, 8–10 µm wide and 4–5 µm long; cells of hyphal sheath wavy in lateral outline, 3–4 µm thick; medulla 30–80 µm thick, composed of loosely woven, irregularly arranged to more or less periclinal hyphae 4–5 µm thick; clamp connections not observed.

Hymenophore not observed.

Chemistry: no substances detected by TLC.

Distribution and Ecology: —This species is known from several collections growing on soil between bryophytes in the Ecuadorian and Bolivian high Andes.

Etymology: —The epithet refers to the thallus appearing squamulose rather than foliose.

Remarks: — Cora squamiformis is phylogenetically closely related to C. pavonia ( Dal-Forno et al. 2013) and was found with the latter in the same habitat in Ecuador. The two species differ markedly in thallus and lobe size and lobe configuration, with C. pavonia having much larger thalli and lobes not growing close to the ground and lacking sinuouse margins, but having a coarsely undulate surface instead. A particular feature of C. squamiformis appears to be the compacted instead of 'medullary' upper cortex, which at first glance is similar to the cortex of Corella species , but in the latter the cortex is distinctly paraplectenchymatous and lacks free hyphae. Cora bovei from southern Argentina ( Spegazzini 1888) is similar to C. squamiformis in general appearance and cortex structure but, as far as can be judged from the depauperate type material, forms larger lobes with concentrically undulate surface.

Additional specimens examined: — ECUADOR. Napo: Papallacta ; 3300 m; disturbed wet paramo vegetation; 4 July 2010, Lücking 32300 (F) . BOLIVIA. La Paz: Franz Tamayo, Madidi National Park, Sanchez Pass between Pelechuco and Keara; 14° 43' S, 69° 08' W, 4602 m; high mountain vegetation (puna), on ground between mosses; 13 October 2007, Wilk 7587 (F, KRAM) . Eliodoro Camacho, Pumasane, crossroads to Pelechuco and Charazani ; 15° 15' S, 69° 03' W, 4536 m; high mountain vegetation (puna), on ground between mosses; 12 October 2007, Wilk 7446 (F, KRAM) .

Figures

FIGURE 8. Cora squamiformis. A. Specimen in the field (Colombia, Lücking s.n.). B. Specimen with strongly bent and sinuose margins (Colombia, Lücking s.n.). C. Specimen in the herbarium (holotype). Scale in A = 10 mm, in B–C = 5 mm.