Metschnikowia chrysoperlae sp. nov., Candida picachoensis sp. nov. and Candida pimensis sp. nov., isolated from the green lacewings Chrysoperla comanche and Chrysoperla carnea (Neuroptera: Chrysopidae)

Abstract

Fourteen yeast isolates comprising three taxa were cultured from digestive tracts of adult Chrysoperla species (Neuroptera: Chrysopidae) and their eggs. The yeast taxa were distinguished based on an estimated molecular phylogeny, DNA sequences and traditional taxonomic criteria. The new yeasts are closely related to Metschnikowia pulcherrima but are sufficiently distinguished by sequence comparison of rRNA gene sequences to consider them as novel species. Here, three novel species are described and their relationships with other taxa in the Saccharomycetes are discussed. Metschnikowia chrysoperlae sp. nov. (type strain, NRRL Y-27615T=CBS 9803T) produced needle-shaped ascospores and was the only teleomorph found. Large numbers of chlamydospores similar to those observed in M. pulcherrima were also produced. The other two novel species are asexual yeasts, Candida picachoensis sp. nov. (type strain, NRRL Y-27607T=CBS 9804T) and Candida pimensis sp. nov. (type strain, NRRL Y-27619T=CBS 9805T), sister taxa of M. chrysoperlae and M. pulcherrima. A specialized relationship between yeasts and lacewing hosts may exist, because the yeasts were isolated consistently from lacewings only. Although M. chrysoperlae was isolated from eggs and adult lacewings, suggesting the possibility of vertical transmission, no yeast was isolated from larvae.