The Ladybird Project

The Harlequin Ladybird

Harmonia axyridis, better known as the harlequin ladybird, was originally designated as a pest control method for local aphid populations in Europe. However, their populations were loosely controlled and have spread across multiple continents over the past 30 years. Now, they outcompete native ladybird populations and hamper food production within the nation.

The Green Beetle Hanger

Hesperomyces harmoniae, or the green beetle hanger, is an ectoparasite in the order Laboulbeniales that infects adult ladybirds. Research has recently focused on this parasite due to its discovery on the globally invasive harlequin ladybird Harmonia axyridis and for its potential use in studies of co-evolution and biocontrol. Hesperomyces harmoniae are a common parasite to the harlequin ladybird and infects its hosts by penetrating into their exoskeletons, taking in nutrients from exposed body fluids. We aim to follow the spread of athe fungal ectoparasite on invasive ladybirds in Europe. 

The Objective

Wanting to explore the relationship between Harmonia axyridis and Hesperomyces harmoniae, Dr. Danny Haelewaters collected samples and observed the influence that the parasite had on the ladybirds, and determined that there is a negative effect on the survival of ladybirds by the parasitic infection of Hesperomyces. This discovery complemented prior findings that determined that fungal infections decreased mating frequency, winter survival rate, and mobility of ladybirds. This research was the first to explicitly link Hesperomyces infections with increased ladybird mortality, shining a light on this mysterious fungus and its effects.

Distribution of Hesperomyces harmoniae in Europe

Photo Gallery


Haelewaters D, Hiller T, Ceryngier P, Eschen R, Gorczak M, Houston ML, Kisło K, Knapp M, Landeka N, Pfliegler WP, Zach P, Aime MC, Nedvěd O. 2022. Do biotic and abiotic factors influence the prevalence of a common parasite of the invasive alien ladybird Harmonia axyridis? Frontiers in Ecology and Evolution 10: 773423.

Haelewaters D, Van Caenegem W, De Kesel A. 2022. Hesperomyces harmoniae, a new name for a common ectoparasitic fungus on the invasive alien ladybird Harmonia axyridis. Sydowia 75: 53-74. [pdf]

Soares, A. O., Haelewaters, D., Ameixa, O. M. C. C., Borges, I., Brown, P. M. J., Cardoso, P., de Groot, M. D., Evans, E. W., Grez, A. A., Hochkirch, A., Holecová, M., Honěk, A., Kulfan, J., Lillebø, A. I., Martinková, Z., Michaud, J. P., Nedvěd, O., Omkar, Roy, H. E., … Losey, J. E. (2022). A roadmap for ladybird conservation and recovery. Conservation Biology, 00, e13965. [pdf]

Haelewaters D, Hiller T, Pan FY, Pan JY. 2019. Tracking an ectoparasitic fungus of Harmonia axyridis in the USA using literature records and citizen science data. IOBC-WPRS Bulletin 145: 16-21. [pdf]

Haelewaters D, De Kesel A, Pfister DH. 2018. Integrative taxonomy reveals hidden species within a common fungal parasite of ladybirds. Scientific Reports 8(1): 15966.

Haelewaters D, Zhao SY, Clusella-Trullas S, Cottrell TE, De Kesel A, Fiedler L, Herz A, Hesketh H, Hui C, Kleespies RG, Losey JE, Minnaar IA, Murray KM, Nedvěd O, Pfliegler WP, Raak-van den Berg CL, Riddick EW, Shapiro-Ilan DI, Smyth RR, Steenberg T, van Wielink PS, Viglášová S, Zhao Z, Ceryngier P, Roy HE. 2017. Parasites of Harmonia axyridis: current research and perspectives. BioControl 62(3): 355-371.

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