On a new genus of dwarf tarantulas (Araneae: Mygalomorphae: Theraphosidae) endemic from Peru: evidence from morphology and molecular phylogeny, with description of three new species

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  On a new genus of dwarf tarantulas ( Araneae : Mygalomorphae : Theraphosidae ) endemic from Peru: evidence from morphology and molecular phylogeny, with description of three new species Abstract Recent field campaigns conducted in Peru along with the examination of museum specimens allowed us to identify small tarantulas that do not fit with any known Theraphosidae genera. Morphology and additional molecular evidence from the mitochondrial gene COI led us to propose Kiskalla gen. nov . from southern Peru, at Puno region. Three new species of Kiskalla gen. nov . ( K. ignacioi sp. nov ., K. yeisoni sp. nov . and K. zukuapasanka sp. nov .) are herein described, diagnosed and illustrated. Kiskalla gen. nov . differs from the known Theraphosinae genera in the presence of lateral stripes on the abdomen and a small dorsal arrowhead-shaped patch of type III urticating setae, presence of a large number of spines on all legs, short and stout setae on the dorsal metatarsi encirc...

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

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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