First record of Hesperomyces virescens Thaxter (Laboulbeniales: Ascomycetes) on Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae)

Abstract

The laboulbenialean fungus Hesperomyces virescens Thaxter (1891) is reported here for the first time parasitizing the infamous multicolored Asian lady beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae). Laboulbeniales (Ascomycetes) are obligate parasites of arthropods and receive their nutrition through a haustorium, which penetrates the cuticle (Evans, 1988). Weir and Hammond (1997) demonstrated that among the Insecta a wide range of taxa serve as hosts with approximately 80% of all known Laboulbeniales recorded from Coleoptera. Approximately 25% of the Laboulbeniales have been reported as ectoparasites of Staphylinidae and another 25% attacking Carabidae. In the UK, Weir and Beakes (1996) reported Hesperomyces virescens from two species of coccinellids, Adalia bipunctata (L.) and Olla v-nigrum (Mulsant). The species H. virescens is described as one of the few among the Laboulbeniales in which the haustoria form several narrow branches radiating out into the body cavity (Batra, 1979). Kamburov et al. (1967) found that H. virescens caused premature mortality of the coccinellid, Chilocorus bipustulatus L. in Israel where this lady beetle is an important predator of several different citrus scales (Homoptera: Diaspididae).