''Oxyepoecus bidentatus'' is a Neotropical

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of ant in the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

'' Oxyepoecus''. The species is only known from workers from

Paraguay Paraguay (; ), officially the Republic of Paraguay ( es, República del Paraguay, links=no; gn, Tavakuairetã Paraguái, links=si), is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to th ...

Distribution

''Oxyepoecus bidentatus'' is known from three localities of the

an dry Chaco. Because the maximal distance between localities was 340 km, ''O. bidentatus'' is suspected to be widely distributed in

xeromorphic A xerophyte (from Greek ξηρός ''xeros'' 'dry' + φυτόν ''phuton'' 'plant') is a species of plant that has adaptations to survive in an environment with little liquid water, such as a desert such as the Sahara or places in the Alps or the ...

Chacoan forests, even if rarely found.

Description

Its worker

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

places the species within the ''rastratus'' species-group. ''Oxyepoecus bidentatus'' is the only species of the genus to have both the dorsal surface of the head entirely covered by sculpture and a bidentate subpostpetiolar process. The anterior subpostpetiolar process of '' O. bruchi'' of the ''vezenyii'' species-group is also prominent and bidentate, but the dorsal surface of the head is mainly smooth and shining except for two patches of fine, longitudinal rugulae which do not reach posteriorly to the vertex margin nor laterally to the compound eye. Criteria separating ''O. bidentatus'' from other species of the ''rastratus'' species-group are the

mesopleuron The mesothorax is the middle of the three segments of the thorax of hexapods, and bears the second pair of legs. Its principal sclerites (exoskeletal plates) are the mesonotum (dorsal), the mesosternum (ventral), and the mesopleuron (lateral) on ...

and lateropropodeum covered by longitudinal costae (and not reticulate as for '' O. myops'', '' O. rosai'', and '' O. reticulatus''), and the presence of a reticulate-costulate sculpture on the dorsal surface of the head reaching posteriorly to the vertexal margin and laterally to the compound eye. Gynes and males are unknown

Biology

The fact that workers were extracted from

leaf litter Plant litter (also leaf litter, tree litter, soil litter, litterfall or duff) is dead plant material (such as leaves, bark, needles, twigs, and cladodes) that have fallen to the ground. This detritus or dead organic material and its constituent ...

(

Winkler method The Winkler test is used to determine the concentration of dissolved oxygen in water samples. Dissolved oxygen (D.O.) is widely used in water quality studies and routine operation of water reclamation facilities to analyze its level of oxygen satura ...

) or were collected in pitfall samples, while no gynes were found, suggests that this species nests in the soil, but workers forage in the leaf litter when abiotic conditions are favorable. Localities where the species was found have a mean annual rainfall and temperature ranging from 593 to 887 mm and from 23 to 25 °C, respectively.

References

* {{Taxonbar, from=Q14651755 Myrmicinae Hymenoptera of South America Insects described in 2011