Spiders

Any myrmecologist that spends time in the field studying ants knows from their own experience that there are a lot of spiders in most places where ants are found. With their diversity and abundance, it should not be any surprise there are spiders that feed on ants. The particulars of prey specialization and dependence on ants as prey vary with the spider species and genus, as does the range of ants of that are preyed upon.

Photo Gallery

A female Euryopis spider hangs and feeds on her Camponotus chalceus victim. Photo by Farhan Bokhari.
Spider feeding on a male Rhytidoponera, most likely R. metallica. Photo by Farhan Bokhari.
A Sericomyrmex worker falling prey to a spider. Photo by Philipp Hönle.
A crab spider (top left) has killed a bullet ant queen and at least 2 species of small flies (Milichiidae & Phoridae) have arrived to feed from the carcass and/or lay their eggs. Amazonian Peru. Photo by Alex Wild.
A young spider, Aphantochilus roguersi, of the family Thomisidae (crab spiders), a predator (and mimic) of Cephalotes, photographed in Manaus, Brazil, by Thiago Gomes de Carvalho.
Aphantochilus rogersi is a species of ant-mimicking crab spiders from South America. It is found from Panama to Paraguay. It mimics ants of the genus Cephalotes, which are their preferred prey. It has the unusual behaviour of carrying the dead husks of ants aloft like a protective umbrella. This may camouflage or hide its identity and allow it to approach and overpower other ants, or it may be a form of defence to protect itself from its enemies. Photo by Gil Wizen.

Obligate Ant Predators

Corythalia

Baigorria et al. (2021) suggest that Corythalia conferta may be the first Corythalia species known to specialize in hunting ants. They describe its hunting behavior and habitat, and found that during a 300 hour field study, 86 prey items where recorded, 98.8% of which were ants representing 11 different species.

Zodarion

Spiders of the genus Zodarion (Araneae: Zodariidae) exclusively prey on ants. Pekár et al. (2018) studied various aspects of how these spiders prey on ants:

Zodarion species chase relatively giant and dangerous ants and overcome them by a combination of very fast attack and venom injection (Pekár, 2004a; Pekár, Šedo, Líıznarová, Korenko, & Zdráhal, 2014). The venom functions both to facilitate capture (including the reduction in prey loss due to escape) and to minimize injury to the spider, as ants can counter-attack (Pekáar, 2004b). As a result, we expect the selection for venom adaptation to be very strong and to lead to venom economy through production of very specific compounds.

Myrmecophagous or ant-eating predators have been assumed to be specialized at the family level, that is, to exploit a variety of related ant species. However, our previous studies indicated that Zodarion spiders not only failed to paralyse alternative prey (Pekár, 2004a) but possessed a high capture efficacy on a specific ant genus (e.g., Pekár, Král, & Lubin, 2005), suggesting that they are specialized on a particular subfamily or genus. It appears that ants have exerted selection on venom composition, which leads to increased capture efficacy on the focal ant species but decreased efficacy on other ant species (Pekár et al., 2005).

Data on natural diet obtained by next-generation sequencing and field observations showed that the six Zodarion species exploit different ant species. Their phylogeny, based on mitochondrial and nuclear genes, correlated with the composition of their natural prey, indicating that closely related Zodarion species specialize on similar ant species. Prey-capture parameters differed among Zodarion species suggesting preyspecific efficacy. Similarly, the venom profiles of both low and high molecular compounds differed among species. Only the profiles of low molecular compounds were correlated with capture efficacy parameters, suggesting that the venom of Zodarion spiders contains prey-specific components. Our study suggests that Iberian Zodarion spiders are specialized on particular ant species.

Known Ant Hosts

Ant	Spider Species	Locality	Source
Iberoformica subrufa	Zodarion		Pekár et al. (2018)
Leptogenys processionalis distinguenda	Sicariomorpha maschwitzi		Ott et al. 2015
Linepithema humile	Zodarion sp.		Pekár et al. 2018
Liometopum microcephalum	Micaria sociabilis	Czech Republic	Pekar, 2020

References

Baigorria, J.A., Rubio, G.D., Stolar, C.E., Oklander, L.I. 2021. Notes on the jumping spider Corythalia conferta (Araneae: Salticidae), a possible myrmecophagous specialist in Argentina. Peckhamia 230.1, 1-12.
Cushing, P.E. 2012. Spider-ant associations: An updated review of myrmecomorphy, myrmecophily, and myrmecophagy in spiders. Psyche: A Journal of Entomology 2012, 1–23 (doi:10.1155/2012/151989).
Pekar, S., L. Petrakova, O. Sedo, S. Korenko, and Z. Zdrahal. 2018. Trophic niche, capture efficiency and venom profiles of six sympatric ant-eating spider species (Araneae: Zodariidae). Molecular Ecology. 27:1053-1064. doi:10.1111/mec.14485
Perger, R., Rubio, G.D. 2020. Contributions to the knowledge of Neotropical ant-like spiders: Myrmecotypus tahyinandu sp. n. from Bolivian Chiquitano forest, a new country record for M. niger, and indirect evidence for species-specific mimicry (Araneae: Corinnidae: Castianeirinae). Zootaxa 4790, 151–164 (doi:10.11646/zootaxa.4790.1.9).