A taxonomic review of the genus Myrmelachista (Hymenoptera: Formicidae) in Costa Rica. Author Longino, J. T. text Zootaxa 2006 1141 1 54 http://antbase.org/ants/publications/21030/21030.pdf journal article 21030 323B9B2C-F6AE-40B5-982B-4BBEA5317786 [[ Genus Myrmelachista ]] The above are a set of species described together by Wheeler from material collected by Elisabeth Skwarra in southern Mexico. They are all very similar to plebecula and joycei . I cannot distinguish workers of amicta , skwarrae (and its two subspecies picea and laeta ), and plebecula . The males of skwarrae and plebecula are distinct. The male of skwarrae differs from plebecula in having a basiparamere lobe and distinct (though minute) setose pygostyles. Myrmelachista skwarrae males are more like joycei . They differ from joycei in the relatively thinner and more delicate basiparamere lobe and relatively larger ocelli. If the Mexican forms prove to be geographic variants of plebecula , the latter has priority. On the other hand, M. joycei could prove to be a geographic variant of one of the previously named Mexican forms.