title: Morphological, molecular, and ultrastructural characterization of Rozella rhizoclosmatii, a new species in Cryptomycota.
abstract: Rozella is a genus of unwalled endoparasites of a variety of hosts including Oomycota (Stramenopiles), Blastocladiomycota and Chytridiomycota (Fungi), and one green alga (Coleochaete, Chlorophyceae). It currently includes more than 20 formally described species, and no new species of Rozella have been described since 1987. We discovered a new Rozella species parasitizing Rhizoclosmatium globosum (Chytridiales, Chytridiomycota) and investigated its morphology, ultrastructure, and phylogenetic position. Herein named as Rozella rhizoclosmatii sp. nov., the organism induces hypertrophy of the host. Its zoospore is ultrastructurally similar to that of Rozella allomycis, although it has a unique zoospore ultrastructural feature, a lattice of perpendicular rods about the nucleus. The 18S rDNA molecular sequence of R. rhizoclosmatii is similar to that of the previously sequenced 'Rozella ex Rhizoclosmatium'. This is the first study to inclusively characterize a new species of Rozella with morphological, ultrastructural and molecular data. As this is only the second Rozella species to be examined ultrastructurally, and because it is parasitic on a member of Chytridiomycota and not Blastocladiomycota, this research supports the conservative nature of zoospore ultrastructure to help define the genus.
authors.affiliation: Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL 35487, USA. Electronic address: letch006@ua.edu.
authors.forename: Peter M
authors.initials: PM
authors.lastname: Letcher
authors.affiliation: School of Biology and Ecology, University of Maine, Orono, ME 04469, USA. Electronic address: longcore@maine.edu.
authors.forename: Joyce E
authors.initials: JE
authors.lastname: Longcore
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA. Electronic address: alishaq@umich.edu.
authors.forename: C Alisha
authors.initials: CA
authors.lastname: Quandt
authors.affiliation: Departamento de Genética, Evolução e Bioagentes, Universidade Estadual de Campinas, Campinas, SP, 13082-862, Brazil. Electronic address: domingos@unicamp.br.
authors.forename: Domingos da Silva
authors.initials: DD
authors.lastname: Leite
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA. Electronic address: tyjames@umich.edu.
authors.forename: Timothy Y
authors.initials: TY
authors.lastname: James
authors.affiliation: Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL 35487, USA. Electronic address: mpowell@ua.edu.
authors.forename: Martha J
authors.initials: MJ
authors.lastname: Powell
mesh_terms: D016000:Cluster Analysis; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D005658:Fungi / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000648:ultrastructure; D010802:Phylogeny; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013172:Spores, Fungal / Q000648:ultrastructure*
chemical_list: D004271:DNA, Fungal; D004275:DNA, Ribosomal; D012337:RNA, Ribosomal, 18S
keywords: Lattice; Morphology; Nomenclature; Parasitism; Taxonomy; Zoospore