5. Cheilolejeunea aurifera (Schuster) Ye et al. (2015: 325) .—

Aureolejeunea aurifera Schuster (1978: 429) .

Type:— VENEZUELA. Mérida: Sierra de Santo Domingo, Sierra de Santo Domingo, between Lagunita verde and Laguna Los Patos, on trunk of a large Espeletia humbertii, 3700 m, 1 February 1976, R.M. Schuster & L. Ruíz-Terán 76-945 (holotype F!).— Fig. 4H–N.

Plants light brown, 1.7–2 mm wide. Stems in cross section 120–130 µm in diameter, 16 epidermal cells 60–110 × 30–45 µm; 16 medullary cells, 40–60 × 20–40 µm. Ventral merophytes 4 cells wide. Leaves imbricate, ovate, flat to strongly concave at the apex, 950–1000 × 700–800 µm; margin entire to slightly crenulated for mammilla projection, apex rounded; dorsal and ventral margins curve. Cells of leaf lobe mammillose-papillose on dorsal side, conspicuous trigones; basal cells 15–21 × 12–14 µm, median cells 11–18 × 8–11 µm, marginal cells 7–12 × 7–9 µm. Lobules rectangular, 1/3–1/2 of leaf length, free margin flat, usually ending in a tooth with triangle shape, formed by 2–5 cells at the base and 2–3 cells long, keel slightly arched. Underleaves imbricate, covering up to 1/3 of the adjacent underleaf, orbicular to ovate, 500–550 × 700–750 µm, 6–8 × stem width, margin fully entire; insertion U-shaped. Autoicous. Androecia not seen. Gynoecia on branches, with lejeuneoid innovations, bracts obovate, 840 × 550 µm, apex rounded, lobule 480 × 160 µm, apex acuminate. Perianth 5-keeled, beak long. Vegetative reproduction unknown.

Distribution and habitat:—Neotropical, occurring in Dominican Republic, Costa Rica, Panamá, Colombia, and Venezuela (Bastos 2017, Schuster 1978). In the study area this species grows hanging on tree trunks and branches, in upper montane rainforest, grass páramos, and shrub and cushion páramos, between 3200–4160 m (Gradstein, 2021), in the Puntarenas-Chiriquí province in the Pacific dominion and the Páramo province of SATZ (Fig. 5).

Notes: —The species is characterized by the plants robust, ventral merophyte which is 4 cells wide, cells mammillose-papillose, underleaves entire, and perianth with 5 keels. The species is morphologically similar to C. quinquecarinata, but it differs mainly by the leaf margin slightly crenulate due to the presence of mammillose-papillose cells and the broader ventral merophyte.

Specimens examined:— COLOMBIA. Boyacá: Chinavita, 3350 m, Zipa 259 A (UPTC) . Cundinamarca: Páramo de Sumapaz, 3800 m, Cleef 1700 (COL) . PANAMÁ. Bocas del Toro: Changuinola, 3200 m, De García 376 p. p. (PMA) . VENEZUELA. Merida: Rangel, Sierra de Santo Domingo, 3700 m, 1 February 1976, Schuster 76-912, 946b (F) .