A Classification of the Fern Genus Tectaria (Tectariaceae: Polypodiales) Based on Molecular and Morphological Evidence

Abstract

The pantropical genus Tectaria Cav. (Tectariaceae) is one of the largest fern genera. It has been estimated to contain ca. 210 mostly tropical species in Africa, the Americas, Asia, and the Indian Ocean and Pacific Ocean islands. Tectaria had perhaps been the most confusing fern genus in terms of its circumscription and phylogeny. Recent studies have recircumscribed Tectaria and resolved the relationships within the genus. However, no efforts have been made to propose an infrageneric classification of the genus based on molecular and morphological evidence. In the present study, we synthesize chloroplast and nuclear DNA evidence, morphology, and/or distribution information and divide Tectaria into four subgenera: Tectaria subg. Ctenitopsis (Ching ex Tardieu & C. Chr.) Li Bing Zhang & Liang Zhang (comb. & stat. nov.), Tectaria subg. Phlebiogonium (Fée) Li Bing Zhang & Liang Zhang (comb. & stat. nov.), Tectaria subg. Tectaria, and Tectaria subg. Tectaridium (Copel.) Li Bing Zhang & Liang Zhang (comb. & stat. nov.). The latter three are further divided into seven, two, and two sections, respectively. Sixteen generic names are synonymized to individual infrageneric taxa, while four generic names are only synonymized to Tectaria because of inadequate data. A key to the infrageneric taxa is given. A nomenclatural account of each infrageneric taxon is provided.