Allolecanicillium elzae gen. et sp. nov. (Cordycipitaceae): revised taxonomy with new combinations, its entomopathogenicity and mass production.

Abstract

In a previous study, an isolate identified as Akanthomyces sensu lato, obtained from the citrus blackfly Aleurocanthus woglumi in Brazil, was shown to be pathogenic towards its host. Phylogenetic evidence indicated that this isolate belongs to a new taxon. This study aimed to describe this new taxon based on both morphological and molecular phylogenetic markers, to assess its potential for the biological control of the conehead termite (Nasutitermes corniger) and the citrus orthezia (Praelongorthezia praelonga) and to evaluate substrates for the mass production of this fungus. Phylogenetic analysis based on TEF1, RPB1, RPB2 and ITS partial sequences demonstrated that this new species is related to Lecanicillium aranearum, Lecanicillium araneicola, Lecanicillium rasoulzarei and Lecanicillium spenceae. However, these species form a clade that corresponds to neither Akanthomyces sensu stricto nor Lecanicillium sensu stricto. Therefore, a new genus Allolecanicillium is proposed here to accommodate Allolecanicillium elzae sp. nov., Allolecanicillium aranearum comb. nov., Allolecanicillium araneicola comb. nov., Allolecanicillium rasoulzarei comb. nov. and Allolecanicillium spenceae comb. nov. These species produce dense white to cream mycelia and simple or branched conidiophores bearing cylindrical to fusoid conidia. The sexual morph is known only for the species A. aranearum. Sporulation of A. elzae on vegetable substrates ranged from 1.46×10⁸ conidia/g of substrate (white rice) to 6.42×10⁸ conidia/g of substrate (sugarcane bagasse). Germination rates did not differ significantly among substrates. Despite being pathogenic to P. praelonga and N. corniger, this fungus showed relatively low virulence against these insects under the conditions tested. This research expands our knowledge of the diversity of entomopathogenic fungi, their host spectrum and alternatives for their production, aiming to foster the recognition of these organisms as sustainable biological resources.