Brachymyrmex aphidicola Forel 1909

Brachymyrmex aphidicolaForel 1909.NEW STATUS.Brachymyrmex heerivar.aphidicolaForel 1909: 263. [w syntypes examined, MHNG; San Bernadino, Cordillera, Paraguay (Fiebrig)].Brachymyrmex heerivar.fallaxSantschi 1923a: 665.NEW SYNONYMY.[Holotype examined, NHMB; Paraguay (s. loc.)].

There is little reason to consider Brachymyrmex heeri and B. aphidicola as conspecific, as both species are locally sympatric and morphologically distinct in eastern Paraguay. Brachymyrmex aphidicola is one of the most abundant ground and litter nesting ant species in Paraguayan forests. Brachymyrmex heeri is more rarely collected, the two nest records I have from Paraguay are both arboreal. The two species are easily separated by the pubescence on gastric tergite 1 (= abd. tergite 3), with the pubescence dense on B. heeri and sparse on B. aphidicola. Santschi’s type of B. heeri fallax (NHMB, examined) falls within the range of variation exhibited by B. aphidicola in Paraguay and is synonymized here. It is worth mentioning here that Paraguayan specimens of B. heeri are a close match, in both the worker and queen castes, to Forel’s types of B. heeri (MHNG, examined) described from an introduced population in Switzerland (Forel 1874).

Given the notoriously poor taxonomic state of Brachymyrmex and the ubiquity of B. aphidicola in the region, there may well exist an older name for this species. A thorough taxonomic revision of this genus is sorely needed.