A further new species for the genus Ananteris Thorell, 1891 (Scorpiones: Ananteridae) from a poorly prospected region of Brazilian Amazonia

Posted by
  A further new species for the genus Ananteris Thorell, 1891 (Scorpiones: Ananteridae) from a poorly prospected region of Brazilian Amazonia Abstract  A new species of the genus Ananteris Thorell, 1891 is described from the region which today defines the ‘Reserva Biológica do Río Trombetas’ in the state of Pará, Brazil. The collection of the unique specimen, presently study, took place previously to the definition of this reserve, in a joint field trip with a team of the Instituto Brasileiro de Desenvolvimento Florestal (IBDF). Ananteris antoni sp. n. is described based on one female specimen collected in a zone of dense humid forest, under death log. With this new description, the number of Ananteris species known for the scorpion fauna of Brazil is now raised to 33. Lourenço W. R., 2026. – A further new species for the genus Ananteris Thorell, 1891 (Scorpiones: Ananteridae) from a poorly prospected region of Brazilian Amazonia. Faunitaxys, 14(63): 1 – 5.  https://doi.o...

Colour polymorphism is prevalent on islands but shows no association with range size in web-building spiders

Posted by

 


Colour polymorphism is prevalent on islands but shows no association with range size in web-building spiders

Abstract

One of the most evident sources of phenotypic diversity within a population is colouration, as exemplified by colour polymorphism. This is relevant to a greater extent in animals with visually-biased sensory systems. There is substantial evidence suggesting that different colour morphs can access a broader range of habitats or niches, leading to larger geographic range sizes. However, this hypothesis has been tested in few lineages, comprising species where colour is likely to be involved in sexual selection. Furthermore, some available evidence considers geographical variation as polymorphism, thus limiting our comprehension of how sympatric colour polymorphism can influence a species’ geographic range. Through an extensive systematic literature review and a comparative analysis, we examined the relationship between colour polymorphism and range size or niche breadth in web-building spiders. We identified 140 colour polymorphic spider species, belonging mainly to the families Araneidae and Theridiidae. We found no evidence that colour polymorphic species differ significantly from non-polymorphic species in terms of range size and niche breadth, after accounting for phylogenetic relationships and other covariates. However, we did observe that colour polymorphic species were more likely to be found on islands compared to non-polymorphic species. Overall, our results indicate that the association between colour polymorphism and geographic range size may not exist among web-building spiders, or be as pronounced as in other lineages. This suggests that the strength of the association between colour polymorphism and ecological success might depend on the ecological role that colouration plays in each clade.


Fabian C Salgado-Roa, Devi Stuart-Fox, Thomas E White, Iliana Medina, Colour polymorphism is prevalent on islands but shows no association with range size in web-building spiders, Journal of Evolutionary Biology, 2024;, voae118, https://doi.org/10.1093/jeb/voae118