Phylogeny and morphology of Hirsutella tunicata sp. nov.(Ophiocordycipitaceae), a novel mite parasite from Peru

A new species of Hirsutella was isolated from unidentified mites on Petri plates inoculatedwith soil and root fragments collected from asparagus rhizosphere at Viru´ , Northern Peru.The fungus differs from other Hirsutella species by an envelope surrounding the conidium,conidia dimension and DNA sequences. In PDA cultures, the mycelium produced aerialhyphae with conidiogenous cells mainly at right angles, occasionally showing a secondaryconidiophore. The solitary conidia are cymbiform, slightly apiculate, 5.0e6.0 3.0e4.0 mm.Phylogenetic analyses with partial rRNA and b-tubulin gene sequences confirmed thefungus as an Hirsutella (Ophiocordycipitaceae). Closest species shown by maximum likelihoodand neighbor-joining trees were H. nodulosa and H. aphidis, from which the newspecies differs for conidium or conidiogenous cells dimensions, lack of synnemata andhost type. A recombination event was also detected in the rRNA of the holotype strain,involving Ophiocordyceps sinensis as major parent and O. cochlidiicola as minor parent. Acomplement, inverted insertion was also found in its rRNA, involving part of the ITS2 and5.8S regions, flanked by two short nucleotide arrays. Due to conidia dimension andphylogenetic position, the fungus is described as Hirsutella tunicata sp. nov. A review ofmononematous Hirsutella species is provided.