Pleopeltis

• Authority

  Mickel, John T. & Beitel, Joseph M. 1988. Pteridophyte Flora of Oaxaca, Mexico. Mem. New York Bot. Gard. 46: 1-580.

• Family

  Polypodiaceae

• Scientific Name

  Pleopeltis

• Description

  Genus Description - Epiphytic, rarely epipetric; rhizome long-creeping, branched; rhizome scales concolorous to bi-colorous, non-clathrate to rarely clathrate, peltate, surface hairy, sometimes glabrous, margin entire to fimbriate or erose; fronds simple to pinnatifid, rarely pinnate-pinnatifid, distant to clumped, monomorphic to subdimorphic, stipitate, articulate; blade firm to coriaceous, sparsely to densely scaly with peltate, circular to ovate-lanceolate scales; veins netted, rarely free, areoles with 1-3 free included veins; sori round to oblong, exindusiate, with round, peltate scales, at least in immature son, within costal areoles in one row on each side of costa, at junction of several included veins (compital); sporangia glabrous; spores bilateral, shallowly to prominently verrucate.

• Discussion

  Type: Pleopeltis augusta Humboldt & Bonpland ex Willdenow. Microphlebodium L. D. Gómez, Phytologia 59: 58. 1985. Type: Microphlebodium munchii (Christ) L. D. Gómez.\ Pleopeltis is a segregate genus of Polypodium s.L, with 30-40 (if Lepisorus of Asia is included) species found in the New World and Africa to India and Sri Lanka, usually distinguished by the lamina and sori with peltate, circular scales, the areoles with free, included veins and sori at the junction of several included veins. The generic limits of Pleopeltis are in need of careful study. Some species appear close to species in Microgramma, whereas others resemble species of Polypodium s.s. Copeland included Polypodium munchii as a Microgramma, but we follow A. R. Smith (1981) in considering it to be a Pleopeltis although other than in its peltate paraphyses its form resembles nothing in either of these genera. Polypodium fallax is considered here to be a Pleopeltis on the basis of the caducous, peltate, circular paraphyses in the sori. Polypodium percussum Cavanilles, often placed in Pleopeltis, is here considered to belong to Microgramma. Several species of Pleopeltis appear to hybridize with species of Polypodium s.s. to produce abortive-spored or fertile species in the hybrid genus x Pleopodium (q.v.). The distribution and density of the peltate scales on the blade are important characters for distinguishing species in Pleopeltis. In the key and species descriptions, the terms used to describe the scales are defined as follows: sparse = scales rarely touching and often space between scales for two or more similar scales; scattered = some scales touching and often space between scales for a single similar scale; dense = most scales overlapping other scales and with little or no space for any additional scales. References: Mickel, J. T. & J. M. Beitel. 1987. Notes on x Pleopodium and Pleopeltis in tropical America. Amer. Fern J. 77: 16-27; Weatherby, C. A. 1922. The group of Polypodium lanceolatum in North America. Contr. Gray Herb. 65: 3-14.