Root anatomy of 37 species of Asplenium (Aspleniaceae) from Argentina: Contributions to the systematics and phylogeny of the genus

Abstract

Asplenium L. (Aspleniaceae) is a large fern genus whose systematics is based mainly in leaf and reproductive characters. In Aspleniaceae, the root anatomy allows delimit the two genera, Asplenium and Hymenasplenium Hayata. Various root subtypes are recognized in Asplenium, according to the layers and number of asplenium sclereids that constitute the inner cortex. In order to assess the potential use of root features in the taxonomy and the phylogenetic relationships within Asplenium, the roots of the 37 species inhabiting Argentina were studied. Observations were carried out employing light microscopy. Various root subtypes were registered. Only in few instances the root subtypes were shared by closely phylogenetically related species, being in the majority of cases homoplastic characters. The root subtype was not related to the plant habit.