Taxonomic review of the ant genus Paratrechina, with a description of a new species from Africa

Abstract

With the recent finding of Paratrechina (broad sense) paraphyly, only Paratrechina longicornis remained in a redefined genus. As one of the most widely distributed ant species due to human transfer around the world, there is much interest in the biology of P. longicornis. One issue concerning P. longicornis has been as to where exactly the species is native, with both African and Asian native ranges being invoked in the literature. Here we report the discovery of a second species within Paratrechina. This species, P. zanjensis, is native to Africa (known from Angola, Mozambique and Tanzania), where it appears to be a dry miombo woodland species. Given the discovery of this new species, a reevaluation of the morphological definition of Paratrechina is provided; also provided is an updated generic level identification key. Given the available distribution information on P. longicornis, we conclude that P. longicornis remains most likely native to southeastern Asia, and that the discovery of a new species native to Africa makes Paratrechina yet another example of an ant genus that possesses an Afro-Asian distribution.

Genetic Diversity and Wolbachia Infection Patterns in a Globally Distributed Invasive Ant

“…High heterozygosity of workers, close association with humans, and high adaptability in disturbed environments of this species may help explain to some extent how this ant spread rapidly around the world even prior to the 20 th century (Weber, 1939; Harris and Berry, 2005; Lester, 2005; Wetterer, 2008; Pearcy et al, 2011). While the precise native range of this ant has been a source of debate and remains uncertain, distribution records of P. longicornis and its closest relatives suggest either a Southeast Asian or African origin (Wetterer, 2008; LaPolla et al, 2010; LaPolla et al, 2013; LaPolla and Fisher, 2014). A comprehensive phylogeographic study of P. longicornis is needed to help identify more precisely where the species originated as well as its subsequent dispersal routes around the globe.…”

Then there were five: a reexamination of the ant genus Paratrechina (Hymenoptera, Formicidae)

“…A review of the argument that Paratrechina longicornis is Asian in origin is provided by Wetterer (2008) and LaPolla et al (2013) (i.e., on the observation that Paratrechina longicornis has only been found in undisturbed habitats in tropical Asia). However, since Paratrechina zanjensis appears to be a miombo woodland specialist and its sister taxon is almost certainly Paratrechina longicornis , it raises the possibility that Paratrechina longicornis might be an African woodland specialist as well.…”

“… LaPolla et al (2013) provided a diagnosis for Paratrechina , which was based on the only two species known from the genus at that time: Paratrechina longicornis (Latreille, 1802) and Paratrechina zanjensis LaPolla, Hawkes & Fisher, 2013. Based on both morphological similarity and molecular data (Ward, unpublished data), it would appear that those two species are sister taxa, so the earlier diagnosis provided for the genus was morphologically restrictive compared to what we now know is a morphologically more diverse genus.…”

“…With our placement of Paratrechina kohli into Paratrechina and the description of two endemic Malagasy species, the center of Paratrechina diversity is now squarely in the Afrotropical and Malagasy regions, which raises some interesting questions as to the origin of the now pantropical Paratrechina longicornis ( LaPolla et al 2013 ). A review of the argument that Paratrechina longicornis is Asian in origin is provided by Wetterer (2008) and LaPolla et al (2013) (i.e., on the observation that Paratrechina longicornis has only been found in undisturbed habitats in tropical Asia). However, since Paratrechina zanjensis appears to be a miombo woodland specialist and its sister taxon is almost certainly Paratrechina longicornis , it raises the possibility that Paratrechina longicornis might be an African woodland specialist as well.…”

“…In all other Paratrechina workers only five mandibular teeth are present. Males are known only from Paratrechina longicornis ( LaPolla et al 2013 ), so it is impossible at this time to discuss general male characteristics for this genus.…”