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bioRxiv · 10.1101/2025.03.28.645512

Genomics and reproductive biology of Leptopilina malgretoutensis Buffington, Lue, Davis & Tracey sp. nov. (Hymenoptera: Figitidae): An asexual parasitoid of Caribbean Drosophila

Abstract

Drosophila and parasitic wasps in the genus Leptopilina have long been a model for understanding host-parasite interactions. Indeed, parasitic wasps are important drivers of ecological and evolutionary processes broadly, but we are generally lacking information about the diversity, natural history, and evolution of these relationships. We collected insects from the Caribbean Island of Saint Lucia, home to the eastern Caribbean dunni subgroup of Drosophila: a clade long appreciated for its recent patterns of speciation and adaptation. Here we present an integrative approach that incorporates natural history, taxonomy, physiology, and genomics to describe Leptopilina n. sp. Buffington, Lue, Davis & Tracey sp. nov. (Hymenoptera: Figitidae), a virulent parasitoid of dunni group flies, especially Drosophila antillea. Leptopilina n. sp. is nested within an early-branching clade of Leptopilina, offering insights into the evolution of this important genus of Drosophila parasitoids. We present a high-quality assembly for this wasps 1Gbp genome, and for its bacterial endosymbiont: Wolbachia strain "wLmal". Furthermore, we show that wLmal induces parthenogenesis in the wasp, and that these wasps are reliant upon their Wolbachia infections to produce female offspring. Finally, comparison to historical museum specimens indicate that Leptopilina n. sp. had been collected approximately 40 years prior from the nearby island of Guadeloupe and were also asexually reproducing. This work represents one of only a handful of studies in which field biology, taxonomy, systematics, genomics, and experimental biology are integrated into a species description: showcasing the possibilities for biodiversity research in the genomic era.

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BibTeXRIS

Lindsey, A. R., Lue, C.-H., Davis, J. S., Borjon, L. J., Mauthner, S. E., Fricke, L. C., Eads, L., Murphy, M., Drown, M. K., Faulk, C., Buffington, M. L., Tracey, W. D.. 2025-03-30. Genomics and reproductive biology of Leptopilina malgretoutensis Buffington, Lue, Davis & Tracey sp. nov. (Hymenoptera: Figitidae): An asexual parasitoid of Caribbean Drosophila. https://doi.org/10.1101/2025.03.28.645512

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