Pseudomyrmex oculatus

AntWiki: The Ants --- Online
Jump to navigation Jump to search
Pseudomyrmex oculatus
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Pseudomyrmecinae
Genus: Pseudomyrmex
Species: P. oculatus
Binomial name
Pseudomyrmex oculatus
(Smith, F., 1855)

Pseudomyrmex oculatus casent0005875 profile 1.jpg

Pseudomyrmex oculatus casent0005875 dorsal 1.jpg

Specimen labels


A widespread and common species that nests in dead twigs or branches of trees.


Ward (1989) - This common, widely distributed species shows considerable geographical variation (particularly in size, sculpture, color, and head shape), but it is at once recognizable by the distinctive shape of the petiolar node. The sudden, subangulate juncture of the dorsal and posterior faces of the node is seen in no other related species. Also characteristic of P. oculatus are the elongate eyes (see REL and REL2 values), relatively broad head, the (typically) punctate-opaque sculpture of the head, and the shape of the postpetiole in lateral view (summit of postpetiolar node displaced posteriorly relative to other species in the P. oculatus group, except P. schuppi).


Ward (1989) reported specimens from Belize, Bolivia, Brazil, Colombia, Costa Rica, Ecuador, French Guiana, Guatemala, Guyana, Honduras, Mexica, Nicaragua, Panama, Peru, Trinidad and Venezuela.

Latitudinal Distribution Pattern

Latitudinal Range: 23.009808° to -31.632389°.

Tropical South

Distribution based on Regional Taxon Lists

Neotropical Region: Belize, Bolivia, Brazil (type locality), Colombia, Costa Rica, Ecuador, French Guiana, Guatemala, Guyana, Honduras, Mexico, Nicaragua, Panama, Peru, Suriname, Trinidad and Tobago, Venezuela.

Distribution based on AntMaps


Distribution based on AntWeb specimens

Check data from AntWeb


Ward (1989) - P. oculatus is typically found nesting in dead twigs or branches, in rain forest or at the edge of rain forest, less frequently in open or drier habitats. Specific nest-site records include dead twigs of Ficus, Hampea, Inga, Vochysia, and various unidentified lianas; I found one colony in the dead leaf sheath of a Seheelea palm.

De Oliveira et al. (2015), studying ant occupancy of Cecropia trees in southwest Bahia, Brazil, found a colony of Pseudomyrmex oculatus nesting in a Cecropia pachystachya tree.



The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

  • advena. Pseudomyrma advena Smith, F. 1855c: 157 (q.) BRAZIL. Junior synonym of oculatus: Forel, 1911e: 277.
  • oculatus. Pseudomyrma oculata Smith, F. 1855c: 159, pl. 13 (w.q.) BRAZIL. Combination in Pseudomyrmex: Kempf, 1961a: 375. Senior synonym of advena: Forel, 1911e: 277; of dolichopsis, implicata: Kempf, 1961a: 375; of altinoda, tuberculata, wessoni: Ward, 1989: 422.
  • dolichopsis. Pseudomyrma dolichopsis Forel, 1899c: 87 (w.) COSTA RICA. Junior synonym of oculatus: Kempf, 1961a: 375.
  • implicata. Pseudomyrma dolichopsis var. implicata Forel, 1911e: 277 (w.) BRAZIL. Junior synonym of oculatus: Kempf, 1961a: 375.
  • altinoda. Pseudomyrma sericea var. altinoda Mann, 1916: 427 (w.) BRAZIL. Combination in Pseudomyrmex: Kempf, 1972a: 223. Junior synonym of oculatus: Ward, 1989: 422.
  • tuberculata. Pseudomyrma wessoni var. tuberculata Enzmann, E.V. 1944: 98, pl. 4, fig. 25 (w.) PERU. Combination in Pseudomyrmex: Kempf, 1972a: 226. Junior synonym of oculatus: Ward, 1989: 422.
  • wessoni. Pseudomyrma wessoni Enzmann, E.V. 1944: 97, pl. 3, fig. 10 (w.) PERU. Combination in Pseudomyrmex: Kempf, 1972a: 226. Junior synonym of oculatus: Ward, 1989: 422.

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



Ward (1989) - measurements (n=24). HL 0.94-1.09, HW 0.73-0.91, MFC 0.017-0.031, CI 0.77-0.87, OI 0.57-0.61, REL 0.55-0.62, REL2 0.67-0.78, OOI (-0.20)-0.37, VI 0.72-0.81, FCI 0.021-0.037, SI 0.46-0.50, SI2 0.62-0.72, FI 0.40-0.44, PDI 0.97-1.40, MPI 0.032-D.056, NI 0.72-0.81, PLI 0.86-1.01, PWI 0.66-0.82, PPWI 1.35-1.61.

diagnosis. Medium to large species, for the oculatus group (HW 0.73-0.93), with broad head (CI 0.77-0.87) and with large, elongate eyes which tend to protrude conspicuously from the sides of the head and which typically (but not always) reach the level of the median ocellus, when head is held in full-face view; occipital margin flat to moderately concave; funicular segments II and III about as long as broad, or nearly so. Fore femur relatively slender (FI 0.40-0.44); metanotal groove moderately impressed; basal face of propodeum flat to weakly convex (lateral view), conspicuously elevated anteriorly above level of mesonotum; basal face of propodeum usually exceeding length of the declivitous face and rounding into the latter, which is laterally submarginate. Petiolar node high and subangulate, with distinctive lateral profile: anterior face smoothly continuous with the flattened, posteriorly uplifted dorsal face which itself rounds sharply into the vertical posterior face; anteroventral petiolar process conspicuous, variable in shape (from bluntly rounded to slightly recurved and hook-like); postpetiole broader than long, in lateral view appearing rather high, with the convex, gradually ascending anterorlorsal face rounding into a more steeply descending posterior face.

Head densely punctate and typically opaque; becoming sublucid on upper third of head in some individuals, because of shiny interspaces between some of the punctures. Mesosoma punctate to coriarious-imbricate and predominately opaque; petiole, postpetiole, and gaster subopaque, covered with numerous fine piligerous punctures. Erect pilosity and appressed pubescence common on most of body, including mesosoma dorsum. Medium to dark brown, the antennae, tibiae, and tarsi variably lighter, often contrastingly so; pronotum and parts of head sometimes lighter in color than gaster; mandibles pale luteous.

Type Material

Ward (1989):

Two syntype worker " Santarem, Brazil (Bates) (The Natural History Museum) [Examined]. One syntype worker here designated LECTOTYPE.

Pseudomyrma dolichopsis Forel, 1899:87. Syntype workers. Suerre. Jimenez, Costa Rica (Alfaro) (Musee d'Histoire Naturelle Genève, Museo Civico di Storia Naturale, Genoa) [Examined].

Pseudomyrma dolichopsis var. implicata Forel, 1911:277. Two syntype workers, Amazonas (Bates) (MHNG) [Examined]. One syntype worker here designated LECTOTYPE.

Pseudomyrma sericea var. altinoda Mann, 1916:427. Syntype workers Porto Velho, Rio Madeira, Brazil (Manr. & Baker) (Museum of Comparative Zoology) [Examined].

Pseudomyrma wessoni Enzmann, 1945:97. Syntype queen, Peru, (MCZC) [Examined].

Pseudomyrma wessoni var. tuberculata Enzmann, 1945:98. Holotype worker, Peru [Not examined].

Lectotypes of both P. oculatus and P. implicatus are designated because the apparent type series of these taxa contain more than one species. In the BMNH, under P. oculatus, I found three species: (1) two syntype workers of what is here interpreted to be P. oculatus, from Santarem, Brazil; (2) an alate queen of Pseudomyrmex peperi (Forel), a Central American acacia-ant labelled (obviously erroneously) "Santarem"; and (3) four workers of Pseudomyrmex filiformis, two of which (from Villanova, Brazil) were labelled as types of P. oculatus. The type series of P. implicatus in MHNG contains two species: (1) two workers of P. oculatus; and (2) one worker of Pseudomyrmex curacaensis. For nomenclatural stability I have chosen as lectotypes of P. oculatus and P. implicatus those workers which correspond to the species described (at least as a queen) and illustrated (as a worker, under the name P. advena) by F. Smith (1855). The choice of lectotypes is also consistent with Kempf's (1961) concept of P. oculatus, which was based on an examination of material in the Hope Collection, Oxford (OXUM) which Kempf considered to represent part of the type series of P. oculatus.

The syntype queen of P. wessoni (Enzmann) is clearly conspecific with P. oculatus. Unfortunately, the type of P. wessoni tuberculatus (Enzmann) cannot be located, and second-guessing the identity of Enzmann's creations is an unsatisfying task. Nevertheless there are enough features of the original description (broad head; large eyes; densely punctate, opaque head; petiolar profile similar to that of P. wessoni) to support synonymy under P. oculatus.


References based on Global Ant Biodiversity Informatics

  • Adams B. J., S. A. Schnitzer, and S. P. Yanoviak. 2016. Trees as islands: canopy ant species richness increases with the size of liana-free trees in a Neotropical forest. Ecography doi: 10.1111/ecog.02608
  • Adams B. J., S. A. Schnitzer, and S. P. Yanoviak. 2019. Connectivity explains local ant community structure in a Neotropical forest canopy: a large-scale experimental approach. Ecology 100(6): e02673.
  • Antoniazzi R., R. N. S. L. Garoo, W. Dattilo, S. P. Ribeiro, and F. S. Neves. 2019. Ant species richness and interactions in canopies of two distinct successional stages in a tropical dry forest. The Science of Nature 106: 20
  • Arruda F. V., M. A. Pesquero, D. G. Marcelino, G. A. Leiter, J. H. C. Delabie, and R. Fagundes. 2015. Size and condition of bamboo as structural factors behind the vertical stratification of the bamboo-nesting ant community. Insectes Sociaux DOI 10.1007/s00040-015-0440-4
  • Basset Y., L. Cizek, P. Cuenoud, R. K. Didham, F. Guilhaumon, O. Missa, V. Novotny, F. Odegaards, T. Roslin, J. Schmidl et al. 2012. Arthropod diversity in a tropical forest. Science 338(6113): 1481-1484.
  • Bezdeckova K., P. Bedecka, and I. Machar. 2015. A checklist of the ants (Hymenoptera: Formicidae) of Peru. Zootaxa 4020 (1): 101–133.
  • Brandao, C.R.F. 1991. Adendos ao catalogo abreviado das formigas da regiao neotropical (Hymenoptera: Formicidae). Rev. Bras. Entomol. 35: 319-412.
  • Cancino, E.R., D.R. Kasparan, J.M.A. Coronado Blanco, S.N. Myartseva, V.A. Trjapitzin, S.G. Hernandez Aguilar and J. Garcia Jimenez. 2010. Himenópteros de la Reserva “El Cielo”, Tamaulipas, México. Dugesiana 17(1):53-71
  • Castano-Meneses, G., M. Vasquez-Bolanos, J. L. Navarrete-Heredia, G. A. Quiroz-Rocha, and I. Alcala-Martinez. 2015. Avances de Formicidae de Mexico. Universidad Nacional Autonoma de Mexico.
  • Chacon de Ulloa P., A. M. Osorio-Garica, R. Achury, and C. Bermudez-Rivas. 2012. Hormigas (Hymenoptera: Formicidae) del Bosque seco tropical (Bs-T) de la cuenca alta del rio Cauca, Colombia. Biota Colombiana 13(2): 165-181.
  • Coelho M. S., G. W. Fernandes, J. C. Santos, and J. H. C. Delabie. 2009. Ants (Hymenoptera: Formicidae) as bioindicators of land restoration in a Brazilian Atlantic forest fragment. Sociobiology 54(1): 51-63.
  • Dattilo W. et al. 2019. MEXICO ANTS: incidence and abundance along the Nearctic-Neotropical interface. Ecology
  • Del Toro, I., M. Vazquez, W. Mackay, P. Rojas, and R. Zapata-Mata. "Hormigas (Hymenoptera: Formicidae) de Tabasco: explorando la diversidad de la mirmecofauna en las selvas tropicales de baja altitud." Dugesiana 16, no. 1 (2009): 1-14.
  • Del Toro, I., M. Vázquez, W.P. Mackay, P. Rojas and R. Zapata-Mata. Hormigas (Hymenoptera: Formicidae) de Tabasco: explorando la diversidad de la mirmecofauna en las selvas tropicales de baja altitud. Dugesiana 16(1):1-14.
  • Enzmann E. V. 1944. Systematic notes on the genus Pseudomyrma. Psyche (Camb.) 51: 59-103.
  • Escalante Gutiérrez J. A. 1993. Especies de hormigas conocidas del Perú (Hymenoptera: Formicidae). Revista Peruana de Entomología 34:1-13.
  • Fernández, F. and S. Sendoya. 2004. Lista de las hormigas neotropicales. Biota Colombiana Volume 5, Number 1.
  • Forel A. 1906. Fourmis néotropiques nouvelles ou peu connues. Annales de la Société Entomologique de Belgique 50: 225-249.
  • Forel A. 1912. Formicides néotropiques. Part IV. 3me sous-famille Myrmicinae Lep. (suite). Mémoires de la Société Entomologique de Belgique. 20: 1-32.
  • Franco W., N. Ladino, J. H. C. Delabie, A. Dejean, J. Orivel, M. Fichaux, S. Groc, M. Leponce, and R. M. Feitosa. 2019. First checklist of the ants (Hymenoptera: Formicidae) of French Guiana. Zootaxa 4674(5): 509-543.
  • INBio Collection (via Gbif)
  • Ibarra-Manriquez, G., and R. Dirzo. 1990. Plantas mirmecofilas arboreas de la estacion de biologia Los Tuxtlas, Veracruz, Mexico. Revista de Biologia Tropical 38: 79-82.
  • Jeanne R. J. 1979. A latitudinal gradient in rates of ant predation. Ecology 60(6): 1211-1224.
  • Kaspari M., D. Donoso, J. A. Lucas, T. Zumbusch, and A. D. Kay. 2012. Using nutritional ecology to predict community structure: a field test in Neotropical ants. Ecosphere 3(11): art.93.
  • Kempf W. W. 1961. Estudos sôbre Pseudomyrmex. III. (Hymenoptera: Formicidae). Studia Entomologica 4: 369-408.
  • Kempf, W.W. 1972. Catalago abreviado das formigas da regiao Neotropical (Hym. Formicidae) Studia Entomologica 15(1-4).
  • Larsen, A., and S. M. Philpott. 2010. Twig-nesting ants: the hidden predators of the coffee berry borer in Chiapas, Mexico. Biotropica 42: 342-347.
  • Livingston G. F., S. M. Philpott, and A. de la Mora Rodriguez. 2012. Do species sorting and mass effects drive assembly in tropical agroecological landscape mosaics? Biotropica 45(1): 10-17.
  • Longino J. T. 2013. Ants of Nicargua. Consulted on 18 Jan 2013.
  • Longino J. T., and R. K. Colwell. 2011. Density compensation, species composition, and richness of ants on a neotropical elevational gradient. Ecosphere 2(3): 16pp.
  • Longino J. et al. ADMAC project. Accessed on March 24th 2017 at
  • Lopes M. C., G. P. A. Lamarre, C. Baraloto, P. V. A. Fine, A. Vincentini, and F. B. Baccaro. 2019. The Amazonas-trap: a new method for sampling plant-inhabiting arthropod communities in tropical forest understory. Entomologia Experimentalis et Applicata
  • Maes, J.-M. and W.P. MacKay. 1993. Catalogo de las hormigas (Hymenoptera: Formicidae) de Nicaragua. Revista Nicaraguense de Entomologia 23.
  • Marinho C. G. S., R. Zanetti, J. H. C. Delabie, M. N. Schlindwein, and L. de S. Ramos. 2002. Ant (Hymenoptera: Formicidae) Diversity in Eucalyptus (Myrtaceae) Plantations and Cerrado Litter in Minas Gerais, Brazil. Neotropical Entomology 31(2): 187-195.
  • Mirmecofauna de la reserva ecologica de San Felipe Bacalar
  • Morini M. S. de C., C. de B. Munhae, R. Leung, D. F. Candiani, and J. C. Voltolini. 2007. Comunidades de formigas (Hymenoptera, Formicidae) em fragmentos de Mata Atlântica situados em áreas urbanizadas. Iheringia, Sér. Zool., Porto Alegre, 97(3): 246-252.
  • Munhae C. B., Z. A. F. N. Bueno, M. S. C. Morini, and R. R. Silva. 2009. Composition of the Ant Fauna (Hymenoptera: Formicidae) in Public Squares in Southern Brazil. Sociobiology 53(2B): 455-472.
  • Neves F. S., K. S. Queiroz-Dantas, W. D. da Rocha, and J. H. C. Delabie. 2013. Ants of Three Adjacent Habitats of a Transition Region Between the Cerrado and Caatinga Biomes: The Effects of Heterogeneity and Variation in Canopy Cover. Neotrop Entomol 42: 258–268.
  • Pires de Prado L., R. M. Feitosa, S. Pinzon Triana, J. A. Munoz Gutierrez, G. X. Rousseau, R. Alves Silva, G. M. Siqueira, C. L. Caldas dos Santos, F. Veras Silva, T. Sanches Ranzani da Silva, A. Casadei-Ferreira, R. Rosa da Silva, and J. Andrade-Silva. 2019. An overview of the ant fauna (Hymenoptera: Formicidae) of the state of Maranhao, Brazil. Pap. Avulsos Zool. 59: e20195938.
  • Reis P. C. J., W. D. Darocha, L. Falcao, T. J. Guerra, and F. S. Neves. 2013. Ant Fauna on Cecropia pachystachya Trécul (Urticaceae) Trees in an Atlantic Forest Area, Southeastern Brazil. Sociobiology 60(3): 222-228.
  • Rodriguez-Garza J. A., and J. J. Reynoso-Campos. 2013. Hormigas (Hymenoptera: Formicidae) del género Pseudomyrmex encontradas en el estado de Quintana Roo, México. In Formicidae de Mexico (eds. M. Vasquez-Bolanos, G. Castano-Meneses, A. Cisneros-Caballero, G. A. Quiroz-Rocha, and J. L. Navarrete-Heredia) p21-32.
  • Rojas P., C. Fragoso, and W. P. MacKay. 2014. Ant communities along a gradient of plant succession in Mexican tropical coastal dunes. Sociobiology 61(2): 119-132.
  • Silvestre R., C. R. F. Brandão, and R. R. Silva da 2003. Grupos funcionales de hormigas: el caso de los gremios del cerrado. Pp. 113-148 in: Fernández, F. (ed.) 2003. Introducción a las hormigas de la región Neotropical. Bogotá: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt, xxvi + 424 pp.
  • Suguituru S. S., D. R. de Souza, C. de Bortoli Munhae, R. Pacheco, and M. S. de Castro Morini. 2011. Diversidade e riqueza de formigas (Hymenoptera: Formicidae) em remanescentes de Mata Atlântica na Bacia Hidrográfica do Alto Tietê, SP. Biota Neotrop. 13(2): 141-152.
  • Vasconcelos, H.L. and J.M.S. Vilhena. 2006. Species turnover and vertical partitioning of ant assemblages in the Brazilian Amazon: A comparison of forests and savannas. Biotropica 38(1):100-106.
  • Vasconcelos, H.L., J.M.S. Vilhena, W.E. Magnusson and A.L.K.M. Albernaz. 2006. Long-term effects of forest fragmentation on Amazonian ant communities. Journal of Biogeography 33:1348-1356
  • Vittar, F. 2008. Hormigas (Hymenoptera: Formicidae) de la Mesopotamia Argentina. INSUGEO Miscelania 17(2):447-466
  • Vittar, F., and F. Cuezzo. "Hormigas (Hymenoptera: Formicidae) de la provincia de Santa Fe, Argentina." Revista de la Sociedad Entomológica Argentina (versión On-line ISSN 1851-7471) 67, no. 1-2 (2008).
  • Vásquez-Bolaños M. 2011. Lista de especies de hormigas (Hymenoptera: Formicidae) para México. Dugesiana 18: 95-133
  • Ward P. S. 1990. The Ant Subfamily Pseudomyrmecinae (Hymenoptera: Formicidae): Generic Revision and Relationship to Other Formicids. Systematic Entomology 15: 449-489
  • Ward P. S. 1992. Ants of the genus Pseudomyrmex (Hymenoptera: Formicidae) from Dominican amber, with a synopsis of the extant Antillean species. Psyche (Cambridge) 99: 55-85
  • Ward, P. S. 1989. Systematic Studies on Pseudomyrmecine Ants: Revision of the Pseudomyrmex Oculatus and P. Subtilissimus Species Groups with Taxonomic Comments on Other Species. Questiones Entomologicae 25: 393-468
  • Wheeler W. M. 1907. A collection of ants from British Honduras. Bulletin of the American Museum of Natural History 23: 271-277.
  • Wheeler W. M. 1918. Ants collected in British Guiana by Mr. C. William Beebe. Journal of the New York Entomological Society 26: 23-28.
  • Yanoviak S. P., and M. Kaspari. 2000. Community structure and the habitat templet: ants in the tropical forest canopy and litter. Oikos 89: 259-266.