Revision of The Genus Salpichlaena J. Sm. (Blechnaceae, Pteridophyta)

Abstract

Salpichlaena J. Sm. (Blechnaceae) is a genus of climbing fern that grows in Central and South America. The number of species recognized for this genus varies according to different authors from one to four. The goal of this work was to provide a systematic revision of the genus Salpichlaena in order to contribute to the knowledge of the fern biodiversity in America. For this purpose morphological, anatomical and palynological characters were analyzed in material from the geographical distribution of Salpichlaena. Herbarium specimens were treated according to the standard techniques for LM and SEM studies. The type specimens and the original descriptions were consulted to determine the applications of names. Two species are recognized, S. volubilis (Kaulf.) J. Sm. and S. hookeriana (Kuntze) Alston. Salpichlaena hookeriana differs from S. volubilis by pronounced foliar dimorphism (the fertile pinnules are much reduced), the presence of foliar buds on sterile basal pinnules, ovate costular scales and the presence of glandular hairs on the abaxial surface of the costa. The spores are monolete in both taxa, with rugulate-granulate perispore and superficial spherules. Salpichlaena volubilis is widely distributed in Central and South America, from Guatemala and Caribbean Islands, up to southern Brazil and Bolivia, across a wide altitudinal range of 200 to 1900 m. Salpichlaena hookeriana grows from Colombia, Venezuelan Guyana, Suriname, British Guiana, North Brazil to Peru and Bolivia, at altitudes up to 800 m. The diagnostic characters, illustrations and distribution maps of both species are given.