New member of Gromochytriales (Chytridiomycetes) - Apiochytrium granulosporum nov. gen. et sp

Sergey A Karpov (1, 2) , David Moreira (3) , Maria A Mamkaeva (2) , Olga V Popova (4) , Vladimir V Aleoshine (4, 1) , Purificacion Lopez-Garcia (3)

1 RAS - Russian Academy of Sciences [Moscow]
2 SPbU - St Petersburg State University
3 ESE - Ecologie Systématique et Evolution
4 MSU - Lomonosov Moscow State University

Molecular phylogenetic analysis of 18S rRNA gene sequences of nearly any species of Chytridiomycota has typically challenged traditional classification and triggered taxonomic revision. This has often led to the establishment of new taxa which, normally, appear well supported by zoospore ultrastructure as diagnostic character. To construct a meaningful and comprehensive classification of Chytridiomycota, the combination of molecular phylogeny and morphological studies of traditionally defined chytrid species is needed. In this work, we have studied morphological and ultrastructural features based on light and transmission electron microscopy as well as molecular phylogenetic analysis of a parasite of the yellow-green alga Tribonema gayanum (strain X-124 CCPP ZIN RAS) morphologically similar to Rhizophydium granulosporum. Phylogenetic analysis of the 18S rRNA gene sequence of this strain supports that it represents a new genus and species affiliated to the recently established order Gromochytriales. The ultrastructure of X-124 confirms its phylogenetic position sister to Gromochytrium and serves as the basis for the description of the new genus and species Apiochytrium granulosporum.

Mots clés: chytrids; molecular phylogeny; ultrastructure

Domaines: Systématique, phylogénie et taxonomie

Sergey A Karpov, David Moreira, Maria A Mamkaeva, Olga V Popova, Vladimir V Aleoshine, et al.. New member of Gromochytriales (Chytridiomycetes) - Apiochytrium granulosporum nov. gen. et sp. Journal of Eukaryotic Microbiology, 2019, 66 (4), pp.582-591. ⟨10.1111/jeu.12702⟩. ⟨hal-02108862⟩