First record of Thaumasia Perty, 1833 nursery web spider (Araneae: Pisauridae) preying upon Polistes canadensis (Linnaeus, 1758) (Hymenoptera: Vespidae) in the Neotropical region

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  First record of Thaumasia Perty, 1833 nursery web spider (Araneae: Pisauridae) preying upon Polistes canadensis (Linnaeus, 1758) (Hymenoptera: Vespidae) in the Neotropical region Abstract Thaumasia Perty, 1833 are opportunistic spiders that inhabit the Neotropical region. This study reports a spider of the genus Thaumasia preying upon Polistes canadensis (Linnaeus, 1758) in semiarid region of Brazil. A spider of the genus Thaumasia was observed moving rapidly from the fountain's water surface to capture an individual of P. canadensis . After successfully capturing the wasp, Thaumasia sp. was observed partially perched on the wall of the fountain, with the prey still on the water surface and trapped by its chelicerae. The pedipalps and chelicerae of Thaumasia sp. manipulated the head of P. canadensis , which stopped moving shortly after being captured, probably because of the action of the spider's venom. The study records a wasp in the diet of Thaumasia based on the ca...

Dysdera parthenogenetica sp. nov. (Araneae, Dysderidae): A Unique Case of Parthenogenesis in Spiders

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Dysdera parthenogenetica sp. nov. (Araneae, Dysderidae): A Unique Case of Parthenogenesis in Spiders

Abstract

We studied the parthenogenetic lineages of the spider Dysdera hungarica (Araneae: Dysderidae). Based on our data, we consider them to constitute a separate taxon, Dysdera parthenogenetica sp. nov. Morphologically, the new species differs mainly by slightly reduced female copulatory organs. The ovaries contain meiotic cells, suggesting that automictic thelytoky occurs in this species. D. parthenogenetica sp. nov. colonised areas west of the ancestral sexual species D. hungarica, especially the Pannonian region; the distribution areas of these species show minimal overlap. The distribution pattern of D. parthenogenetica sp. nov. suggests that the obligate thelytoky in this species originated through geographic thelytoky. D. parthenogenetica sp. nov. has been found in a significantly larger variety of habitats than D. hungarica, including agroecosystems. Therefore, the parthenogenesis of D. parthenogenetica sp. nov. is associated with the ability to populate even habitats without tree or bush cover, often disturbed, which is unfavourable for other Dysdera species. According to the analysis of selected nuclear (ITS2) and mitochondrial markers (COI), D. parthenogenetica sp. nov. showed low genetic diversity (single COI haplotype and two closely related ITS2 haplotypes) in contrast to the ancestral D. hungarica. By separation of D. parthenogenetica sp. nov., D. hungarica becomes a paraphyletic species. D. hungarica is thus one of the first documented cases of paraspecies among spiders. Although D. parthenogenetica sp. nov. exhibits minimum genetic variation at the analysed molecular markers, it displays considerable karyotype diversity. The transition to parthenogenesis was accompanied by a decrease in diploid number through chromosome fusions. Karyotypes of D. parthenogenetica sp. nov. diverged considerably from those of D. hungarica. Potential hybrids between these species would likely produce gametes with defective genomes. There is also a behavioural barrier between these two taxa. Females of D. parthenogenetica sp. nov. refuse to mate.

Řezáč, M., Král, J., Ávila Herrera, I. M., Forman, M., Řezáčová, V., Gloríková, N., & Heneberg, P. (2025). Dysdera parthenogenetica sp. Nov. (Araneae, Dysderidae): A Unique Case of Parthenogenesis in Spiders. Journal of Zoological Systematics and Evolutionary Research, 2025(1), 9266860. https://doi.org/10.1155/jzs/9266860