First record of Megaselia abdita (Schmitz, 1959) (Diptera: Phoridae) infestation in captive tarantulas (Araneae: Theraphosidae

Posted by
  First record of Megaselia abdita (Schmitz, 1959) (Diptera: Phoridae) infestation in captive tarantulas (Araneae: Theraphosidae Abstract Flies of the genus Megaselia Rondani, 1856 exhibit exceptional ecological flexibility, with certain species acting as facultative parasites. This study presents the first documented cases of Megaselia abdita (Schmitz, 1959) infesting captive tarantulas (Araneae: Theraphosidae, Ceratogyrus darlingi Pocock, 1897 and Psalmopoeus irminia Saager, 1994) in terrarium settings. Our observations demonstrate that M . abdita colonise artificial habitats and exploit spider hosts similarly to Megaselia scalaris . Citation: Szymański, D.M., Szymański, D., Kłonowski, P. (2026). First record of Megaselia abdita (Schmitz, 1959) (Diptera: Phoridae) infestation in captive tarantulas (Araneae: Theraphosidae). Dipteron, 42, 25-29. https://doi.org/10.5281/zenodo.23137389

Duplication of a conserved mitochondrial enzyme gene arms parasitoid wasps with venom cytotoxicity and oogenesis regulation

Posted by

 


Duplication of a conserved mitochondrial enzyme gene arms parasitoid wasps with venom cytotoxicity and oogenesis regulation

Abstract

Gene duplication, followed by neofunctionalization, is a key mechanism driving the emergence of evolutionary novelties. Despite its significance, the molecular and functional processes underlying this phenomenon remain incompletely understood. By tracing the evolutionary history of cysteine-S-conjugate beta-lyase genes within the kynurenine aminotransferase family, we identified a gene duplication event in parasitoid wasps of the Chalcidoidea superfamily. Notably, a single-copy, highly conserved mitochondria-localized physiological gene underwent a significant duplication, resulting in one copy being recruited into the venom system and acquired cytotoxicity against wasps' hosts. Through this neofunctionalization process, we observed several key evolutionary changes, including loss of ancestral mitochondrial localization and enzyme activity, acquisition of a secretory signal peptide, shift in expression pattern, positive selection, and the establishment of evolutionary acquired protein–protein interactions. Additionally, we found that another duplicate copy was specialized in wasps' ovary and repurposed for oogenesis regulation. Our study offers a detailed insight into the genetic and molecular mechanisms that drive functional diversification during the evolution of gene families.

Song, J., Qi, Z., He, C., Luo, G., Yuan, B., Xiao, S., Yang, Y., Wang, F., Ye, G., Fang, Q., & Yan, Z. (2025). Duplication of a conserved mitochondrial enzyme gene arms parasitoid wasps with venom cytotoxicity and oogenesis regulation. Proceedings of the National Academy of Sciences, 122(39), e2512820122. https://doi.org/10.1073/pnas.2512820122