Monographs Details:
Authority:
Mickel, John T. & Smith, Alan R. 2004. The pteridophytes of Mexico. Mem. New York Bot. Gard. 88: 1-1054.
Mickel, John T. & Smith, Alan R. 2004. The pteridophytes of Mexico. Mem. New York Bot. Gard. 88: 1-1054.
Family:
Polypodiaceae
Polypodiaceae
Description:
Species Description - Rhizomes long-creeping, 1–2 mm diam.; rhizome scales brown, concolorous, 1–2 mm long, lanceolate, entire; fronds monomorphic or only slightly dimorphic, coriaceous; stipes stramineous, 1/10–1/3 the frond length, mostly 1–5 cm long; blades lanceolate, 12–22 x 0.8–2.2 cm, apices acute to long-acuminate, bases very gradually cuneate, midribs with scattered lanceolate scales 1–2 mm long, adaxially with the veins often readily visible; indument abaxially of sparse round scales 0.3 mm diam. and rare lanceolate scales 1 mm long, margins fimbriate, indument adaxially absent; sori round, slightly sunken, with dense filiform hairs (scales) branching from the bases into several reddish brown hair-like segments, nearly obscuring sporangia; 2n=74 (CR, Peru).
Species Description - Rhizomes long-creeping, 1–2 mm diam.; rhizome scales brown, concolorous, 1–2 mm long, lanceolate, entire; fronds monomorphic or only slightly dimorphic, coriaceous; stipes stramineous, 1/10–1/3 the frond length, mostly 1–5 cm long; blades lanceolate, 12–22 x 0.8–2.2 cm, apices acute to long-acuminate, bases very gradually cuneate, midribs with scattered lanceolate scales 1–2 mm long, adaxially with the veins often readily visible; indument abaxially of sparse round scales 0.3 mm diam. and rare lanceolate scales 1 mm long, margins fimbriate, indument adaxially absent; sori round, slightly sunken, with dense filiform hairs (scales) branching from the bases into several reddish brown hair-like segments, nearly obscuring sporangia; 2n=74 (CR, Peru).
Discussion:
Polypodium percussum Cav., Descr. Pl. 243. 1801. Pleopeltis percussa (Cav.) Hook. & Grev., Icon. Filic. 1: t. 67. 1828. Type. Peru [incorrectly stated as Marianas by Cavanilles]. Ne´e s.n. (MA, seen and commented on by Christensen, Dansk Bot. Ark. 9(3): 11. 1937).
See discussion under generic description for comments on taxonomic position. Microgramma percussa is distinct by its sori with dense cushion of hair-like trichomes, small round abaxial blade scales, and coriaceous blades, usually with long-acuminate apices. The venation of M. percussa is often readily visible in dried fronds adaxially, contrasting with other scaly-bladed species of Microgramma.
Distribution:
Mexico North America| Bolivia South America| Brazil South America| Peru South America| Amazonas Ecuador South America| French Guiana French Guiana South America| Suriname South America| Guyana South America| Venezuela South America| Colombia South America| Panama Central America| Puntarenas Costa Rica Central America| Nicaragua Central America| Honduras Central America| Belize Central America| Guatemala Central America|
Mexico North America| Bolivia South America| Brazil South America| Peru South America| Amazonas Ecuador South America| French Guiana French Guiana South America| Suriname South America| Guyana South America| Venezuela South America| Colombia South America| Panama Central America| Puntarenas Costa Rica Central America| Nicaragua Central America| Honduras Central America| Belize Central America| Guatemala Central America|