Myrmelachista nodigera Mayr

Wild, A. L., 2007, A catalogue of the ants of Paraguay (Hymenoptera: Formicidae)., Zootaxa 1622, pp. 1-55 : 44

Myrmelachista nodigera Mayr 1887.

Myrmelachista nodigera Mayr 1887: 529. [holotype w examined, NHMW; Santa Catharina, Brazil, Hetschko] .

Myrmelachista nodigera var. flavicornis Emery 1896b: 638. NEW SYNONYMY. [syntype w examined, MCSN; Concepción, Paraguay (Bohls)] .

Myrmelachista nodigera subsp. pallida Forel 1909: 263. NEW SYNONYMY. [syntype w examined, MHNG; San Bernadino , Cordillera, Paraguay (Fiebrig)] .

Myrmelachista (Decamera) nodigera Mayr. Emery 1925: 33.

Myrmelachista (Decamera) nodigera var. flavicornis Emery . Emery 1925: 33.

Myrmelachista (Decamera) nodigera subsp. pallida Forel . Emery 1925: 33.

Myrmelachista (Hinckisidris) nodigera Mayr. Kempf 1972: 150.

Myrmelachista (Hinckisidris) nodigera var. flavicornis Emery . Kempf 1972: 150.

Myrmelachista (Hinckisidris) nodigera pallida Forel . Kempf 1972: 150.

Worker head shape in Myrmelachista nodigera shows slight allometric variation within nest series, with larger workers having somewhat broader heads, and this variation may have misled Emery and Forel in defining their intraspecific taxa flavicornis and pallida , both from Paraguay. Mayr’s M. nodigera type is a larger and more robust worker than the types of M. flavicornis and M. pallida , yet single nest series I have collected in Canindeyú and San Pedro span the range of variation encompassed by the type specimens for all three taxa. Color is also variable within a nest, presumably related to worker age, so Forel’s distinction of M. pallida on color is baseless. In my estimation the known Paraguayan collections related to M. nodigera comprise a single species.

Forel’s type of Myrmelachista arborea (MHNG examined) from San Bernadino is a single queen unassociated with workers. Judging from the shape of the petiole, M. arborea may be the queen of M. nodigera . Further collections to obtain complete nest series will help establish the identity of this species.