Nomamyrmex esenbeckii (Westwood 1842)

Wild, Alexander L., 2007, A catalogue of the ants of Paraguay (Hymenoptera: Formicidae), Zootaxa 1622, pp. 1-55 : 43

Nomamyrmex esenbeckii (Westwood 1842) .

Labidus esenbeckii Westwood 1842: 75 .

Eciton crassicornis F. Smith 1855: 163 . NEW SYNONYMY.

Eciton (Labidus) esenbeckii (Westwood) . Emery 1890b: 39.

Eciton (Labidus) crassicornis F. Smith. Wheeler 1916: 324 .

Eciton (Holopone) esenbeckii (Westwood) . Santschi 1925b: 11.

Eciton (Nomamyrmex) esenbeckii (Westwood) . Borgmeier 1936: 55.

Eciton (Nomamyrmex) crassicornis F. Smith. Borgmeier 1936: 55 .

Nomamyrmex crassicornis (F. Smith) . Borgmeier 1953: 14.

Nomamyrmex esenbecki (Westwood) . Borgmeier 1953: 14.

Nomamyrmex esenbecki crassicornis (F. Smith) . Borgmeier 1955: 139.

The collections of Nomamyrmex that I have examined from Paraguay fall neatly into two species corresponding most commonly to N. esenbeckii and more rarely to N. hartigii . Watkins (1976) and Borgmeier (1955) provide characters to separate the species.

In contrast, literature records of Nomamyrmex from Paraguay pertain to three forms, N. hartigii (Borgmeier 1955, Santschi 1916), N. esenbeckii (Borgmeier 1955, Santschi 1929a), and N. esenbeckii crassicornis (Forel 1906, Forel 1908b, Forel 1909). The literature records of N. esenbeckii crassicornis , a subspecies generally known from the more tropical regions of South America, are based on Forel’s identifications. Thus, the presence of three forms in the literature is likely an artifact of differing conceptions on the part of earlier taxonomists. Regardless of these conceptual differences, the subspecies of N. esenbeckii are largely allopatric across the Neotropics (Watkins 1976). Gordon Snelling, who has examined material from throughout the region, provides a detailed case for the synonymy of all of them at www.armyants.org. I concur with Snelling’s reasoning and synonymize N. crassicornis under N. esenbeckii here.