Rhizidium phycophilum, a new species in Chytridiales

Abstract

Molecular and ultrastructural investigations are revealing unrealized diversity among chytrids as the taxonomic revision of order Chytridiales (Chytridiomycota) progresses. During a biodiversity survey of soil-inhabiting chytrids in Australia an undescribed chytrid was isolated from a soil sample collected in a cool temperate rainforest of New South Wales, Australia. Combined zoospore ultrastructure analysis and molecular phylogenetic analyses of partial LSU rRNA and ITS1-5.8S-ITS2 sequences demonstrated this chytrid was a new species within Chytridiales and possessed distinctive zoospore architecture previously unknown. Herein we delineate a new Rhizidium species in Chytridiales based on molecular monophyly and unique subcellular organization of the zoospore.

• chytrid
• phylogeny
• 28S rDNA
• vesicles
• zoospore

This study was supported by the National Science Foundation through REVSYS grant DEB-0516173 and MRI grant DEB-0500766. We express our appreciation to Joyce Longcore for providing chytrid cultures and the Assembling the Fungal Tree Of Life (AFTOL) Project, Duke University, (NSF DEB-0228668) for access to their database. In addition Kathryn Picard thanks the Howard Hughes Medical Institute for a Science Program Grant given to The University of Alabama and the National Science Foundation’s REU and Bridge to the Doctorate programs for both training opportunities and support.