Pseudomyrmex gracilis

Distribution
This taxon was described from Central America.

It is found in the United States, Paraguay, Ecuador, Brazil, Bolivia, Uruguay, Colombia, Peru, Venezuela, Argentina, Suriname, French Guiana, Guyana, Mexico, Belize, Guatemala,  El Salvador, Honduras, Nicaragua, Panama, Costa Rica, Dominican Republic, Greater Antilles, Barbados, Trinidad and Tobago, Guadeloupe

Nomenclature

 *  gracilis. Formica gracilis Fabricius, 1804: 405 (w.) CENTRAL AMERICA. Wheeler, W.M. & Bailey, 1920: 256 (l.); Wheeler, G.C. & Wheeler, J. 1956: 385 (l.). Combination in Leptalea: Erichson, 1839: 309; in Pseudomyrma: Roger, 1862c: 289; in P. (Clavanoda): Enzmann, E.V. 1944: 61; in Pseudomyrmex: Kusnezov, 1953e: 214. Senior synonym of longinoda: Brown, 1949a: 43; Kempf, 1961a: 370; of variabilis: Ward, 1989: 439; of bicolor, canescens, dimidiata, glabriventris, mexicana, pilosula, sericata, velifera, volatilis and material of the unavailable name guayaquilensis referred here: Ward, 1993: 155; of atrinoda: Wild, 2007b: 55. Current subspecies: nominal plus argentinus. See also: Ward, 1999b: 521.
 * bicolor. Pseudomyrma bicolor Guérin-Méneville, 1844a: 427 (w.) COLOMBIA. Combination in Pseudomyrmex: Kempf, 1958f: 434. Junior synonym of gracilis: Roger, 1862c: 289; Mayr, 1863: 452. Revived from synonymy as subspecies of gracilis: Emery, 1890b: 59; Santschi, 1925d: 223; Wheeler, W.M. 1942: 166. Junior synonym of gracilis: Ward, 1993: 155.
 * sericata. Pseudomyrma sericata Smith, F. 1855c: 159 (w.) BRAZIL. Gallardo, 1932a: 50 (m.). Combination in Pseudomyrmex: Kempf, 1958f: 434. Status as species: Forel, 1912g: 19. Subspecies of gracilis: Emery, 1890b: 60; Santschi, 1916e: 370; Gallardo, 1932a: 48. Junior synonym of gracilis: Ward, 1993: 155.
 * dimidiata. Pseudomyrma dimidiata Roger, 1863a: 177 (w.) COLOMBIA. Combination in Pseudomyrmex: Kempf, 1958f: 434. Subspecies of gracilis: Mayr, 1870a: 406; Forel, 1912g: 19. Junior synonym of gracilis: Ward, 1993: 155.
 * mexicana. Pseudomyrma mexicana Roger, 1863a: 178 (w.) MEXICO. Wheeler, G.C. & Wheeler, J. 1956: 385 (l.); Petralia & Vinson, 1980: 381 (l.). Combination in Leptalea: Smith, M.R. 1951a: 788; in Pseudomyrmex: Kusnezov, 1953e: 214. Subspecies of gracilis: Mayr, 1870a: 409; Emery, 1890b: 45; Forel, 1907e: 7; Creighton, 1950a: 80. Revived status as species: Whitcomb, Denmark, et al. 1972: 31. Junior synonym of gracilis: Ward, 1993: 155. See also: Ward, 1985b: 225.
 * canescens. Pseudomyrma canescens Smith, F. 1877b: 66 (q.) BRAZIL. Combination in Pseudomyrmex: Kempf, 1958f: 434. Junior synonym of gracilis: Ward, 1993: 155.
 * pilosula. Pseudomyrma pilosula Smith, F. 1877b: 62 (w.) BARBADOS. Combination in Pseudomyrmex: Kempf, 1958f: 435. Junior synonym of gracilis: Ward, 1993: 155.
 * variabilis. Pseudomyrma variabilis Smith, F. 1877b: 62 (w.) BARBADOS. Combination in Pseudomyrmex: Kempf, 1958f: 435. Junior synonym of gracilis: Ward, 1989: 439.
 * volatilis. Pseudomyrma volatilis Smith, F. 1877b: 65 (m.) MEXICO. Combination in Pseudomyrmex: Kempf, 1958f: 435. Junior synonym of gracilis: Ward, 1993: 155.
 * glabriventris. Pseudomyrma gracilis var. glabriventris Santschi, 1922b: 345 (w.) BOLIVIA. Combination in Pseudomyrmex: Kempf, 1958f: 434. Junior synonym of gracilis: Ward, 1993: 156.
 * velifera. Pseudomyrma gracilis var. velifera Stitz, 1933: 68 (q.) GUATEMALA. Combination in Pseudomyrmex: Kempf, 1958f: 434. Junior synonym of gracilis: Ward, 1993: 156.
 * atrinoda. Pseudomyrma gracilis var. atrinoda Santschi, 1934c: 26 (w.q.) BRAZIL. Combination in Pseudomyrmex: Kempf, 1958f: 434. Junior synonym of gracilis: Wild, 2007b: 55.
 * longinoda. Pseudomyrma gracilis var. longinoda Enzmann, E.V. 1944: 87 (w.) PERU. Junior synonym of gracilis: Brown, 1949a: 43; Kempf, 1961a: 370.

The lectotype worker of P. gracilis, although lacking a head, seems to correspond rather well to the concept of P. gracilis which has become prevalent in publications. The mesosoma, postpetiole, and gaster are dark brown to black, the petiole a contrasting light castaneous brown; fine, silvery (not black) pilosity covers most of the body, and the associated piligerous punctures subdue the lustre of the integument; the petiole is narrow and slender, with a long anterior peduncle; and the pronotum is margined laterally but not sharply so. I do not attach much taxonomic significance to the light-colored petiole. The P. gracilis lectotype worker agrees well with material from Kartabo, Guyana (leg. Wheeler) in which there is variable infuscation of the petiole. A second worker in the P. gracilis "type series" in ZMUC, with a red "TYPE" label, but no locality or identification label, is in fact not conspecific (it is a worker of Pseudomyrmex maculatus (F. Smith) and should be excluded from consideration as type.

There is a bewildering and variable array of forms, variously described as subspecies or "varieties" of P. gracilis, which require detailed taxonomic study. I suspect that most of these will prove to be synonyms of a single polytypic species (P. gracilis), but at this stage there is insufficient information about the intra- and inter-specific components of this variation. One unambiguous synonymy can be established here: the lectotype worker of P. variabilis (F. Smith) in BMNH agrees very closely with that of P. gracilis, the only substantial difference being that the P. variabilis petiole is black. I have designated a lectotype of P. variabilis because a second worker glued to the same card (and bearing therefore the same type label as P. variabilis) is that of a different species - P. maculatus (F. Smith)! I have printed a lectotype label for P. variabilis and marked the card shared by the two specimens in such a way that the P. maculatus worker is clearly excluded as a type specimen of P. variabilis''.

Type Material
Ward (1985):

Syntype worker, Essequibo, Guyana (Smidt) [Examined]; here designated Lectotype.

Pseudomyrma variabilis F. Smith, 1877. Syntype worker, "Barbadoes" [Examined]; here designated Lectotype.