Diversity of Batrachospermales (Rhodophyta) in the Iberian Peninsula

Abstract

Fifty-four streams of the Iberian Peninsula were investigated to document the species richness and phylogeny of Batrachospermum and morphologically similar genera, determine phylogenetic affinities of taxa and infer biogeographic trends. Species were identified using morphology and DNA sequence data for the rbcL gene as follows: Batrachospermum gelatinosum, B. pozoazulense, Paludicola keratophyta, Sheathia arcuata, S. boryana, S. confusa, Torularia atra, Virescentia helminthosa, V. vogesiaca, and Volatus carrionii. Batrachospermum gelatinosum and S. boryana were most frequent (sampled from 16 and 11 streams, respectively). Torularia atra and V. vogesiaca were each collected in a single stream, whereas the other five taxa were present in three to six streams. Virescentia vogesiaca is well known from other parts of Europe but had previously not been reported from the Iberian Peninsula. Biogeographic trends based on DNA sequence data show a flora with most species being well represented in parts of Europe, two taxa (B. gelatinosum and V. carrionii) that are shared between Europe and North America, one between Europe and South America (Paludicola keratophyta) and one cosmopolitan species (T. atra). Previous studies reported twelve taxa in the region using current taxonomy. This study has confirmed seven of these taxa with sequence data and morphology.