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Abstract Parasitoid wasps are among the most speciose animals, yet have relatively few available genomic resources. We report a draft genome assembly of the wasp Diachasma alloeum (Hymenoptera: Braconidae), a host-specific parasitoid of the apple maggot fly Rhagoletis pomonella (Diptera: Tephritidae), and a developing model for understanding how ecological speciation can “cascade” across trophic levels. Identification of gene content confirmed the overall quality of the draft genome, and we manually annotated ∼400 genes as part of this study, including those involved in oxidative phosphorylation, chemosensation, and reproduction. Through comparisons to model hymenopterans such as the European honeybee Apis mellifera and parasitoid wasp Nasonia vitripennis, as well as a more closely related braconid parasitoid Microplitis demolitor, we identified a proliferation of transposable elements in the genome, an expansion of chemosensory genes in parasitoid wasps, and the maintenance of several key genes with known roles in sexual reproduction and sex determination. The D. alloeum genome will provide a valuable resource for comparative genomics studies in Hymenoptera as well as specific investigations into the genomic changes associated with ecological speciation and transitions to asexuality.
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This content will become publicly available on December 12, 2025
Speciation Genes
Speciation genes, or loci harboring allelic variants that have contributed to the evolution of reproductive isolation between lineages, have been identified by recent efforts in many systems. The normal functions of these genes and their patterns of evolutionary change confirm several classic theoretical predictions and spur new questions about the process of speciation.
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- Award ID(s):
- 2222464
- PAR ID:
- 10587581
- Publisher / Repository:
- Elsevier
- Date Published:
- Edition / Version:
- 2
- Volume:
- 4
- ISBN:
- 9780128096338
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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