A species description and taxonomic uncertainty through analyses of Linepithema males.
The neotropical genus Linepithema is mostly known by the globally invasive Linepithema humile — the Argentine ant. However, the remaining twenty species in the genus are fairly typical, unassuming ants, overshadowed by their infamous relative. A recent paper by Stefano Cantone and Andrea Di Giulio offers a closer look at some of these lesser known Linepithema as well as the naming of completely new species.
Male ants are very understudied and are usually overlooked, but this paper focused solely on the males of the Linepithema fuscum species group. Males of the fuscum group stand out from those of all other Linepithema by a much longer and skinnier appearance, an additional cell in their forewings, and differing genital morphology. Cantone and Di Giulio compare the genital morphology of several species in the fuscum group, providing a key to the males of the six mainland species and describing a new species. The new Linepithema paulistana can be distinguished by an additional tooth on the volsella (a reproductive piece), and is notable for extending the known range of the fuscum group into eastern South America. The authors also suggest that the genus may be in need of a revision, given the strong differences between the males of the fuscum group and other Linepithema.
The study is available here.