Nephridiophagids (Chytridiomycota) reduce the fitness of their host insects

New nephridiophagid genera (Fungi, Chytridiomycota) in a mallow beetle and an earwig

Nephridiophagids are unicellular fungi (Chytridiomycota) that infect the Malpighian tubules of insects. Most species have been found in cockroach hosts and belong to the genus Nephridiophaga. Three additional genera have been described from beetles and an earwig. Here, we characterise morphologically and molecular phylogenetically the nephridiophagids of the European earwig Forficulaauricularia and the mallow beetle Podagricamalvae. Their morphology and life cycle stages resemble those of other nephridiophagids, but their rRNA gene sequences support the existence of two additional genera. Whereas the earwig nephridiophagid (Nephridiochytriumforficulaegen. nov. et sp. nov.) forms a sister lineage of the Nephridiophaga cluster, the mallow beetle nephridiophagid (Malpighivincopodagricaegen. nov. et sp. nov.) represents the earliest divergent lineage within the nephridiophagids, being sister to all other species. Our results corroborate the hypothesis that different insect groups harbour distinct nephridiophagid lineages.