Trichomanes rigidum Sw.

Authority

Proctor, George R. 1989. Ferns of Puerto Rico and the Virgin Islands. Mem. New York Bot. Gard. 53: 1-389.

Family

Hymenophyllaceae

Scientific Name

Trichomanes rigidum Sw.

Description

Species Description - Rhizome short and woody, decumbent, ascending, or erect, bearing numerous wiry prop roots and clothed at apex with stiff, lustrous brown, pluricellular hairs. Fronds usually fasciculate (rarely somewhat apart from elongation of the rhizome), 10-35 cm long, rigidly erect or spreading, of stiff, elastic texture, the firmly membranous tissue dark green and hygroscopic; stipes mostly 4-15 cm long, 0.5-1.5 mm in diam., wiry, flexuous, deciduously brown-hairy, not winged. Blades ovate to deltate or broadly lanceolate, 6-20 cm long, 4-15 cm broad, acuminate at apex, finely 3- to 4-pinnate (or small forms 2-pinnate-pinnatifid), the vascular parts more or less glandular setulose on abaxial side; rhachis terete, not winged but narrowly marginate toward distal end, bearing a few scattered hairs like those of stipe; pinnae close, usually inequilateral at base and acuminate at apex, the divisions narrowly linear; ultimate segments very numerous, mostly 0.3-0.5 mm broad, simple or forked, longpointed at apex, often revolute in drying. Sori often numerous, subaxillary, reflexed; involucres narrowly funnelform, somewhat compressed and narrowly marginate, the apex tmncate and slightly 2-lobed; receptacle becoming very long-exserted.

Discussion

Type. Swartz, from Jamaica without exact locality (S, photo U S ; isotypes SBT; Herb. Willd. 20202-1, B, photos G H , US).

Syn. Trichomanes compressum Desvaux, Ges. Naturf Freunde Berlin Mag. 5: 329. 1811. (Type from "America calidiore," not seen.)

Trichomanes mandioccanum Raddi, Pl. bras. nov. gen. 1: 64, t. 79, fig 2. 1825. (Type. Raddi, from Brazil, not seen.)

Trichomanes krugii Christ ex Urban, Bot. Jahrb. Syst. 24: 90. 1897. (Syntypes cited from Cuba, Martinique, St. Vincent, and Grenada, not seen.)

Distribution

General Distribution. Pantropical.