First finding of the parasitic fungus Hesperomyces virescens (Laboulbeniales) on native and invasive ladybirds (Coleoptera, Coccinellidae) in South Africa.

Danny Haelewaters,Ingrid A Minnaar,Susana Clusella-Trullas

doi:10.1051/parasite/2016005

Danny Haelewaters, Ingrid A Minnaar + Show 1 more

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https://doi.org/10.1051/parasite/2016005

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Abstract

Hesperomyces virescens is a fungal ectoparasite (Laboulbeniales) that infects adult ladybirds. Research has recently focused on this parasite due to the discovery of its prevalence on the globally invasive harlequin ladybird Harmonia axyridis and for its potential use in studies of co-evolution and pathogen spread. We collected adults from ten species of ladybirds in the Western Cape Province, South Africa, and screened for the presence of H. virescens. Infections with H. virescens were found in the samples of two species, H. axyridis and the native Cheilomenes propinqua. This marks the first record of H. virescens on H. axyridis from the African continent and the first record on Cheilomenes worldwide.

Highlights

Hesperomyces virescens Thaxt. (Ascomycota: Laboulbeniomycetes: Laboulbeniales) [25] is an obligate fungal ectoparasite that infects adults of ladybirds (Coleoptera: Coccinellidae) [4]
Most Laboulbeniales exhibit great host specificity and are restricted to a particular species or genus, H. virescens reportedly infects several ladybird species from around the world. It was described in 1891 by Thaxter [25] on Chilocorus stigma (Say, 1835) [as C. bivulnerus] from California, USA, and in 2002 it was found for the first time to parasitize the invasive harlequin ladybird, Harmonia axyridis in Ohio, USA [9]
Almost a third of the specimens of H. axyridis collected in Stellenbosch were infected by H. virescens while none of the other alien species showed signs of infection (Table 1)

Summary

Introduction

Hesperomyces virescens Thaxt. (Ascomycota: Laboulbeniomycetes: Laboulbeniales) [25] is an obligate fungal ectoparasite that infects adults of ladybirds (Coleoptera: Coccinellidae) [4]. Most Laboulbeniales exhibit great host specificity and are restricted to a particular species or genus, H. virescens reportedly infects several ladybird species from around the world. It was described in 1891 by Thaxter [25] on Chilocorus stigma (Say, 1835) [as C. bivulnerus] from California, USA, and in 2002 it was found for the first time to parasitize the invasive harlequin ladybird, Harmonia axyridis in Ohio, USA [9]. The fungus completes its entire life cycle on the integument of a living host where individual fruiting bodies or thalli are formed directly from ascospores (for detailed morphology see [7]). Non-random distribution patterns of thalli on the body of both sexes of the host suggest that direct transmission occurs

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