Dennstaedtia

Content

Altitude

Description

Rhizomes creeping or less commonly ascending, usually stout, pubescent, solenostelic; fronds large, often with a bud near the base of each stipe; blades bipinnate to quadripinnate-pinnatifid, chartaceous to coriaceous, glabrous to pubescent; veins free, extending not quite to the segment margins, tips often clavate; sori marginal, without paraphyses, inner and outer indusia forming a cup- or purse-shaped sorus, indusia not greatly modified; spores tetrahedral; x=?.A

A. Mickel, J. T. & Smith, A. R. 2004: The Pteridophytes of Mexico Vol. 88

Discussion

Dennstaedtia is most diversified in the Old World (eastern Asia and the South Pacific), with 20 species in America. In Mexico it most closely resembles Saccoloma, from which it is distinct in the hairy rhizome and the sori at the very margin. Dennstaedtia is probably most closely related to Hypolepis, Pteridium, and Histiopteris, these four genera occupying a relatively basal position (in Dennstaedtiaceae) among the higher leptosporangiate ferns.
We thank Hugo Navarrete of Pontificia Universidad Católica del Ecuador, Quito, for reviewing the manuscript and offering valuable suggestions.

Excluded Species
Dennstaedtia obtusifolia (Humb. & Bonpl. ex Willd.) T. Moore, Index Fil. 306. 1861. Dicksonia obtusifolia Humb. & Bonpl. ex Willd., Sp. Pl., ed. 4, 5(1): 483. 1810. Type. Venezuela. Caracas, Bredemeyer s.n. (B-Willd. 20163!; frag. LE!). Specimens previously considered as this species are here treated under D. cornuta, the true D. obtusifolia being limited to Venezuela, Colombia, Ecuador, and Peru and having rounded (vs. elongate) sori.
B

B. Mickel, J. T. & Smith, A. R. 2004: The Pteridophytes of Mexico Vol. 88

Distribution

México (Country) native and not endemicC

C. Mickel, J. T. & Smith, A. R. 2004: The Pteridophytes of Mexico Vol. 88

Synonymy

Dennstaedtia Bernh., J. Bot. (Schrader) 3(2): 124. 1801