Phylogenetic analysis of the small subunit ribosomal RNA gene of the hyphochytrid Rhizidiomyces apophysatus

The potential relationship of the uniflagellate hyphochytrids with biflagel late stramenopiles is still not clearly resolved. Thus, we have expanded th e number of isolates and taxa of hyphochytrids compared. The phylogenetic a nalysis of the small subunit ribosomal RNA sequence of Rhizidiomyces apophy satus Zopf based on neighbour-joining and parsimony methods showed that Hyp hochytrium catenoides Karling and R. apophysatus are monophyletic and proba bly the closest relatives of the oomycetes. Our data also confirmed the mon ophyly of the stramenopiles, which includes heterokont algae along with non photosynthetic fungallike organisms, namely the Oomycota, Hyphochytriomycot a, and Labyrinthulomycota.