Cheilolejeunea discoidea (Lehm. & Lindenb.) Kachroo & Schuster (1961: 509)

Gil-Novoa, Jorge Enrique & Costa, Denise Pinheiro, 2023, Synopsis of the species of Cheilolejeunea (Marchantiophyta, Lejeuneaceae) in the Pacific dominion and Páramo province of tropical America, Phytotaxa 587 (2), pp. 73-120 : 89

9. Cheilolejeunea discoidea (Lehm. & Lindenb.) Kachroo & Schuster (1961: 509) .—

Jungermannia discoidea Lehm. & Lindenb. (in Lehmann 1834: 47).

Type:— ST. VINCENT: Ad truncus arborum, L. Guilding s.n. (not seen).— Fig. 7J–P .

Plants yellowish green to light brown, 0.4–0.7 mm wide. Stems in cross section 45–52 µm in diameter, 7(–8) epidermal cells, 13–29 × 86–16 µm; 8-9 medullary cells, 6–20 × 4–9 µm. Ventral merophytes 2 cells wide. Leaves suberect to obliquely spreading, ovate-orbicular, flat, 280–3100 × 215–250 µm, margin entire; cells orbicular, subquadrate to hexagonal, without trigones or inconspicuous; basal cells 16–30 × 10–18 µm, median cells 16–24 × 9–20 µm, marginal cells 9–23 × 8–13 µm. Lobules ovate to rectangular, 130–160 µm × 95–1100 µm, free margin involute, apical tooth with 1 cell, blunt. Underleaves distant, ovate, 85–105 × 90–100 µm, 1.5–2.0 × stem width, bifid to 1/4–1/3, with a V-shaped sinus, margin entire, insertion curved. Autoicous. Androecia terminal on main stem or branches, with 3–12 pairs of bracts. Gynoecia with 1–2 lejeuneoid innovations. Perianth pyriform, 5-keeled, keels more strongly developed to apex, beak short. Vegetative reproduction unknown.

Distribution and habitat:—Neotropical, occurring in Costa Rica, Panamá, Brazil, St. Vincent ( Bastos 2017, Schäfer-Verwimp 2014); recorded here as new to Perú and Colombia. Found growing as an epiphyte on tree trunks in the study area in lowland rainforests, from sea level to 600 m, in the Guatuso-Talamanca, Puntarenas-Chiriquí, and Sabana provinces of the Pacific dominion ( Fig. 8 ).

Notes:—Morphologically C. discoidea is very similar to small morphotypes of C. rigidula , the latter differing by plants more robust,>700 µm wide (vs 490–700 µm wide in C. discoidea ), underleaves 2–3 × stem width (not 0.9–2.0×), and dioicous sexual condition (not autoicous).

Specimens examined:— BRAZIL. Pará: Capit „o Poço, 1°46’S, 47°4’W, 40 m, 24 June 2006, Tavares, 950 ( RB). Rio de Janeiro: Carapebus, PARNA Jurubatiba, 22°17’702”S, 41°40’33”W, 4 April 2006, Imbassahy 121 ( RB); Itatiaia, Parque Nacional de Itatiaia , 2400 m, 13 April 2000, Costa 3843 ( RB) . COLOMBIA. Guaviare: San José del Guaviare , 2°34’16.0’’ N, 72°53’09.7’’ W, 252 m, 4 December 2021, Gil-Novoa & Costa 3654 ( UPTC) . COSTA RICA: Guanacaste. Liberia , National Park Rincón de la Vieja, 750–800 m, 1 January 2000, Schäfer-Verwimp & Holz SV /H-0392 (ALCB) . PERU. Loreto: Iquitos, Maynas , 7 August 1984, Timme 4709 ( NY) .

Figures

FIGURE 7. Cheilolejeunea cuspidifera A. Shoot sections in ventral view; B. Perianth with bracts and bracteoles; C. Androecial stem; D- E. Leaves and lobules, F. Ventral merophyte, G. Apex of lobule, H. Underleaf, I. Leaf lobe cells. Cheilolejeunea discoidea J. Cladograph of fertile plants (solid ellipse = androecia, open ellipse = gynoecia with perianth, U= gynoecia without perianth), K. Shoot section in ventral view, L. Perianth with bracts and bracteole, M. Ventral merophyte, N. Leaf and lobule, O. Underleaf, P. Leaf lobe cells. Cheilolejeunea filiformis Q-R. Cladographs of fertile plants (solid ellipse = androecia, open ellipse = gynoecia with perianth), S. Shoot section in ventral view, T. Perianth with bracts and bracteoles, U. Portion of stem with androecium, V. Ventral merophyte and underleaf, X. Lobule, Y. Leaf lobe cells. Cheilolejeunea fragrantíssima Z. Cladograph of fertile plants (solid ellipse = androecia, open ellipse = gynoecia with perianth), AA. Portion of stem with perianth, BB. Portion of stem with androecium, CC. Ventral merophyte, DD. Leaf and lobule, EE. Lobule, FF. Underleaf, GG. Leaf lobe cells.

FIGURE 8. Distribution of Cheilolejeunea cuspidifera, C. discoidea, and C. erostrata in Pacific dominion and Páramo province.