Pseudomyrmex brunneus

Every Ant Tells a Story - And Scientists Explain Their Stories Here
Jump to navigation Jump to search
Pseudomyrmex brunneus
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Pseudomyrmecinae
Genus: Pseudomyrmex
Species: P. brunneus
Binomial name
Pseudomyrmex brunneus
(Smith, F., 1877)

Pseudomyrmex brunneus casent0104806 profile 1.jpg

Pseudomyrmex brunneus casent0104806 dorsal 1.jpg

Specimen labels



Ward (1985) - Similar to Pseudomyrmex ejectus.The major differences between the two species are in the shapes of the propodeum, petiole, and postpetiole (note especially the non-overlapping values of PWI and PPWI). In addition, P. brunneus tends to have a more densely sculptured (and opaque) head than P. ejectus and to exhibit less contrasting light and dark brown coloration on the mesosoma, petiole and post petiole.


Distribution based on Regional Taxon Lists

Neotropical Region: Costa Rica, Greater Antilles, Mexico (type locality).

Distribution based on AntMaps


Distribution based on AntWeb specimens

Check data from AntWeb


Ward (1985) - At Cola de Caballo, near Monterrey, I collected workers and larvae of P. brunneus in dead twigs of a small tree, probably Melia azedarach, and in the dead stalk of an unidentified mint. The latter nest contained a single dealate queen, P. ejectus was also found nesting in a dead mint stalk at this locality.

This appears to be an uncommon Mexican species, which occurs sympatrically with P. ejectus.



The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.

  • brunneus. Pseudomyrma brunnea Smith, F., 1877b: 63 (w.) MEXICO. Emery, 1895c: 270 (q.); Wheeler, G.C. & Wheeler, J. 1956: 382 (l.). Combination in Leptalea: Smith, M.R. 1951a: 788; in Pseudomyrmex: Wheeler, G.C. & Wheeler, J. 1956: 382. Senior synonym of nigrita: Ward, 1985b: 231.
  • nigrita. Pseudomyrma brunnea var. nigrita Enzmann, E.V. 1944: 82, pl. 2, fig. 12 (w.) MEXICO. Combination in Pseudomyrmex: Kempf, 1972a: 216. Junior synonym of brunneus: Ward, 1985b: 231.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.



Ward (1985) - Measurements (n = 10): HL 0.77-0.86, HW 0.67-0.72, MFC 0.012-0.024, CI 0.83-0.90. OI 0.57-0.63, REL 0.51-0.56, REL2 0.58-0.64, OOI 0.67-1.20, VI 0.70-0.78, FCI 0.017-0.035, SI 0.43-0.50, SI2 0.69-0.80, FI 0.41-0.45, PDI 0.56-0.75, MPI 0.052-0.075, NI 0.57-0.65, PLI 0.47-0.58, PWI 0.54-0.65, PPWI 1.26-1.54.

Worker Diagnosis. —Small, brown species, with wide head and broadly rounded occiptal margin (HW 0.67-0.72, CI 0.83-0.90). Similar to p. ejectus F. Smith (q.v.) except as follows: basal face of propodeum between one half and three quarters the length of declivitous face (POI 0.56-0.75); petiole shorter and broader than that of p. ejectus (PWI 0.54-0.65); petiolar node somewhat displaced posteriorly; postpetiole short and wide (PPWI 1.26-1.54). Front of head opaque, densely coriarious-imbricate; sculpture becoming weaker towards the vertex, with scattered, fine punctures on a (usually) sublucid, coriarious background; mesosoma subopaque, coriarious to coriarious-imbricate; petiole, postpetiole, and gaster increasingly (in that order) less coriarious and more smooth and shining. Erect pilosity very sparse; appressed pubescence scattered over body; abdominal tergite IV with appressed hairs separated by about their lengths, and not obscuring the shiny integument. Body dark brown, little or no contrast in color between the head, mesosoma, petiole, postpetiole, or gaster; mandibles and apical ends of tarsi luteous.

Type Material

Ward (1985) - Holotype (unique syntype) worker. Mexico (The Natural History Museum) (Examined).

Pseudomyrma brunnea var. nigrita Enzmann. 1945, p, 82, Syntype workers, Mirador, Mexico (E. Skwarra) (Museum of Comparative Zoology) (Examined).


  • Emery, C. 1895d. Beiträge zur Kenntniss der nordamerikanischen Ameisenfauna. (Schluss). Zool. Jahrb. Abt. Syst. Geogr. Biol. Tiere 8: 257-360 (page 270, queen described)
  • Smith, F. 1877b. Descriptions of new species of the genera Pseudomyrma and Tetraponera, belonging to the family Myrmicidae. Trans. Entomol. Soc. Lond. 1877: 57-72 (page 63, worker described)
  • Smith, M. R. 1951c. Family Formicidae. Pp. 778-875 in: Muesebeck, C. F., Krombein, K. V., Townes, H. K. (eds.) Hymenoptera of America north of Mexico. Synoptic catalogue. U. S. Dep. Agric. Agric. Monogr. 2:1-1420. (page 788, Combination in Leptalea)
  • Ward, P. S. 1985b. The Nearctic species of the genus Pseudomyrmex (Hymenoptera: Formicidae). Quaest. Entomol. 21: 209-246 (page 231, Senior synonym of nigrita)
  • Wheeler, G. C.; Wheeler, J. 1956. The ant larvae of the subfamily Pseudomyrmecinae (Hymenoptera: Formicidae). Ann. Entomol. Soc. Am. 49: 374-398 (page 382, larva described)
  • Wheeler, G. C.; Wheeler, J. 1956. The ant larvae of the subfamily Pseudomyrmecinae (Hymenoptera: Formicidae). Ann. Entomol. Soc. Am. 49: 374-398 (page 382, Combination in Pseudomyrmex)