Joining the dark side: waterfall spiders in subterranean habitats, with the description of a new genus and two new species from Brazil (Araneae: Trechaleidae)

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  Joining the dark side: waterfall spiders in subterranean habitats, with the description of a new genus and two new species from Brazil (Araneae: Trechaleidae) Abstract Trechaleidae is a family of spiders often recognized by its semiaquatic species, but its diversity extends beyond these well-known examples. In this study, we describe Troglotrechalea gen. nov. , a new genus with two novel species, T. faleroae spec. nov. and T. agorai spec. nov. , found exclusively in subterranean habitats within karst formations in central and southeastern Brazil. Both species exhibit pale coloration, but unmodified eyes and legs if compared to other species in the family. The slight degree of troglomorphism, along with their geographic and habitat records, suggests that these species are restricted to hypogean habitats, although they probably move through epigean habitats. Additionally, we report in detail the occurrence of the trechaleid genera Enna O. Pickard-Cambridge, 1897, Heidrunea Brescovi...

A perilous Malagasy triad: a spider (Vigdisia praesidens, gen. and sp. nov.) and an ant compete for termite food

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A perilous Malagasy triad: a spider (Vigdisia praesidens, gen. and sp. nov.) and an ant compete for termite food


ABSTRACT

Ants and termites are insect groups that make up most of the insect biomass in tropical ecosystems. Due to their social structure and abundance, they are some of the most bountiful prey available to other invertebrates such as spiders. However, ants and termites possess dangerous defense strategies, thus limiting their accessibility to general predators. Here, we report on an unexpected finding of a three-way predator-prey-kleptoparasite interaction in Madagascar among a termite Nasutitermes sp. (prey), a previously unknown theridiid spider Vigdisia praesidens gen. nov., sp. nov. (predator), and an ant Pheidole spinosa (kleptoparasite). Our field observations suggest that the spiders are able to detect a damaged termite nest from a distance to disperse onto it and prey on its residents. Kleptoparasitic ants also arrive on the scene to steal from the spiders their termite prey. Both the spider and the ant seem to possess some degree of behavioural prey specialisation for Nasutitermes termites. The here described ecological interaction warrants further study to better understand the exploitation of signals by such phylogenetically diverse arthropods.


Gregorič, M., Yu, K. P., Ravelojaona, J., Agnarsson, I., & Kuntner, M. (2024). A perilous Malagasy triad: a spider (Vigdisia praesidens, gen. and sp. nov.) and an ant compete for termite food. New Zealand Journal of Zoology, 1–12. https://doi.org/10.1080/03014223.2024.2373185