Pseudomyrmex simplex

Prefers to nest in dead twigs as opposed to the hollowed out stems of herbaceous vegetation.

Identification
Ward (1985) - This species is the smallest one of a trio of orange Pseudomyrmex (Pseudomyrmex pallidus, Pseudomyrmex  seminole, P. simplex) which have been confused repeatedly in the United States. P. simplex workers are recognizable by their smooth, shiny, puncticulate head; broad forefemur (FI ≥ 0.45); and shining fourth abdominal tergite which is devoid of a dense mat of appressed pubescence. In addition the workers have long eyes, closely contiguous frontal carinae, a very shallow metanotal groove, and a short petiole and postpetiole. The simplex and delicatulus types share these essential features, along with the other material which I have examined. There is a fair range of variation in size and body proportions (see metrics). P. simplex tends to be lighter in color than related species, and the fuscous patches on abdominal tergite IV are usually conspicuous, at least in Florida populations (less so in Central and South America).

Distribution based on Regional Taxon Lists
Nearctic Region: United States. Neotropical Region: Argentina, Bahamas, Belize, Brazil, Colombia, Costa Rica, Cuba, Dominican Republic, Ecuador, El Salvador, Greater Antilles, Grenada, Guatemala, Haiti, Honduras, Jamaica, Mexico, Panama, Paraguay, Peru, Puerto Rico, Trinidad and Tobago, Venezuela.

It is also found in the United States, Ecuador, Colombia, Peru, Paraguay, Mexico, Belize, Guatemala, El Salvador, Honduras, Panama, Costa Rica, Dominican Republic, Haiti, Greater Antilles, Bahamas, Jamaica, and Trinidad and Tobago.

Biology
Ward (1985) - P. simplex shows a preference for nesting in dead twigs of woody shrubs or trees, rather than in dead stalks of herbaceous plants. In Florida, I have collected nests in dead twigs or stalks of Baccharis halimifolia, Cladium jamaicense, Laguncularia racemosa, Metopium toxiferum and Nectandra coriacea; there are also museum records from Carya floridana and Swietenia mahagoni.

In Costa Rica I recorded nests of P. simplex in dead twigs of Anacardium, Ardisia revoluta, Avicennia germinans, Conocarpus erectus, Gliricidia sepium, Hibiscus tiliaceus, and Terminalia catappa.

Most P. simplex nests I dissected were queenless (indicating a high level of polydomy), some were monogynous, and one contained two functional (i.e. inseminated, with well-developed ovaries) dealate queens.

Alates have been collected in May, June, and September in Florida.

Gillette et al. (2015) in a Chaipas, Mexico field study of twig-nesting ants in coffee plants found P. simplex was by far the most abundant ant in lower elevation (< 1000 m) sites, occupying 80% of all occupied nests.

Koch et al. (2018) sampled this species in Caryocar barsiliense trees, in southeastern Brazil cerrado, as part of a study examining species interactions in ant-plants.

Nomenclature

 *  simplex. Pseudomyrma simplex Smith, F. 1877b: 64 (w.) BRAZIL. Combination in Pseudomyrmex: Kempf, 1972a: 223. Senior synonym of capperi, delicatula, panamensis and material of the unavailable name vittata referred here: Ward, 1985b: 238. See also: Ward, 1992: 75 (specimen in amber).
 * capperi. Pseudomyrma delicatula var. capperi Forel, 1899c: 93 (w.) JAMAICA. Combination in Pseudomyrmex: Kempf, 1972a: 215. Subspecies of flavidula: Wheeler, W.M. 1913d: 240. Junior synonym of simplex: Ward, 1985b: 238.
 * delicatula. Pseudomyrma delicatula Forel, 1899c: 93, pl. 4, fig. 6 (w.q.) JAMAICA. Wheeler, W.M. 1913b: 484 (m.). Combination in Pseudomyrmex: Kempf, 1972a: 215. Subspecies of acanthobius: Forel, 1907e: 7; of flavidulus: Wheeler, W.M. 1913b: 484; Wheeler, W.M. 1913d: 240; Wheeler, W.M. & Mann, 1914: 17. Junior synonym of simplex: Ward, 1985b: 238.
 * panamensis. Pseudomyrma delicatula var. panamensis Forel, 1899c: 93 (w.) GUATEMALA. Combination in Pseudomyrmex: Kempf, 1972a: 215. Junior synonym of simplex: Ward, 1985b: 238.

Type Material
Ward (1985, 1989):

Holotype (unique syntype) worker. Sao Paulo de Olivenca ["St. Paul"], Amazonas, Brazil [Examined].

Pseudomyrma delicatula Forel. 1899. Syntype workers, one dealate queen. Kingston, Jamaica (Forel) [Examined.]

Pseudomyrma delicatula var. panamensis Forel, 1899. Holotype (unique syntype) worker. Pantaleon, Guatemala. 1700 ft (Champion) (MHNG) [Examined].

Pseudomyrma delicatula var. capperi Forel, 1899. Syntype workers. Jamaica (Capper) (MHNG) [Examined].

Pseudomyrma acanthobia race delicatula. var. vittata Forel, 1912. Syntype workers. Ceara, Brazil (Rocha) (MHNG) [Examined].

Worker
Ward (1985) - Measurements (n = 46): HL 0.70-0.92, HW 0.55-0.74, MFC 0.009-0.017, CI 0.75-0.85, OI 0.49-0.55, REL 0.52-0.61, REL2 0.62-0.77, OOI 0.55-1.92, VI 0.68-0.83, FCI 0.013-0.025, SI 0.40-0.48, SI2 0.56-0.72, FI 0.45-0.52, PDI 1.27-1.94, MPI 0.005-0.043, NI 0.53-0.65, PLI 0.50-0.69, PWI 0.39-0.60, PPWI 0.97-1.31.

Diagnosis. —Relatively small species, with moderately elongate head (HW 0.55-0.74, CI 0.75-0.85); median portion of anterior clypeal margin straight, laterally angulate; frontal carinae very closely contiguous (minimum distance between them much less than the basal width of scape); eyes relatively long (REL 0.52-0.61); occipital margin concave, flat, or slightly convex, in full face, dorsal view; lateral margins of pronotum rounded: metanotal groove very weak and shallow; basal face of propodeum longer than declivitous face, and more or less clearly differentiated from it; petiole relatively short, with an anterior peduncle and anteroventral tooth; postpetiole often wider than long, somewhat globose in lateral view. Head predominately smooth and shining; frons with scattered fine punctures of variable size, on a smooth or obsoletely coriarious background; punctures less dense on the vertex, which is smooth and shining; mesosoma and petiole sublucid, dorsally weakly coriarious-punctulate, laterally coriarious-imbricate; postpetiole and gaster more or less smooth and shining. Erect pilosity sparse, lacking on mesonotum, propodeum, mid and hind femora, and (often) petiole: typically a pair of erect setae on pronotum, postpetiole, and adjacent to the eyes. Fine, appressed pubescence very sparse, notably so on postpetiole and abdominal tergite IV. Light orange brown, mandibles and clypeus a paler luteous; a pair of anterolateral fuscous patches usually present (sometimes weak) on abdominal tergite IV.

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.
 * Addison D. S., I. Bartoszek, V. Booher, M. A. Deyrup, M. Schuman, J. Schmid, and K. Worley. 2016. Baseline surveys for ants (Hymenoptera: Formicidae) of the western Everglades, Collier County, Florida. Florida Entomologist 99(3): 389-394.
 * Alayo D. P. 1974. Introduccion al estudio de los Himenopteros de Cuba. Superfamilia Formicoidea. Academia de Ciencias de Cuba. Instituto de Zoologia. Serie Biologica no.53: 58 pp. La Habana.
 * Benitez-Malvido, J., W. Dattilo, A. P. Martinez-Falcon, C. Duran-Barron, J. Valenzuela, S. Lopez, and R. Lombera. 2016. The multiple impacts of tropical forest fragmentation on arthropod biodiversity and on their patterns of interactions with host plants. Plos One 11: e0146461.
 * Brandao, C.R.F. 1991. Adendos ao catalogo abreviado das formigas da regiao neotropical (Hymenoptera: Formicidae). Rev. Bras. Entomol. 35: 319-412.
 * 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., S. Valdes-Rodriguez, A. Hurtado-Giraldo, and M. Cleopatra Pimienta. 2014. Arboreal ants of Gorgona National Park (Pacific of Colombia). Rev. Biol. Trop. 62(1): 277-287.
 * Dattilo W. et al. 2019. MEXICO ANTS: incidence and abundance along the Nearctic-Neotropical interface. Ecology https://doi.org/10.1002/ecy.2944
 * De la Mora A., C. J. Murnen, and S. M. Philpott. 2013. Local and landscape drivers of biodiversity of four groups of ants in coffee landscapes. Biodiv. Conserv. 22: 871-888.
 * De la Mora, A., C. J. Murnen, and S. M. Philpott. 2013. Local and landscape drivers of biodiversity of four groups of ants in Neotropical coffee landscapes. Biodiversity and Conservation 22: 871-888.
 * 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.
 * Deyrup M., C. Johnson, G. C. Wheeler, J. Wheeler. 1989. A preliminary list of the ants of Florida. Florida Entomologist 72: 91-101
 * Deyrup M., L. Davis, and S. Buckner. 1998. Composition of the ant fauna of three Bahamian islands. Proceedings of the seventh symposium on the natural history of the Bahamas. 23-32. Bahamian Field Station, San Salvador, Bahamas
 * Deyrup, M. 2003. An updated list of Florida ants (Hymenoptera: Formicidae). Florida Entomologist 86(1):43-48.
 * Deyrup, M. and J. Trager. 1986. Ants of the Archbold Biological Station, Highlands County, Florida (Hymenoptera: Formicidae). Florida Entomologist 69(1):206-228
 * Enzmann E. V. 1944. Systematic notes on the genus Pseudomyrma. Psyche (Camb.) 51: 59-103.
 * Fernandes I., and J. de Souza. 2018. Dataset of long-term monitoring of ground-dwelling ants (Hymenoptera: Formicidae) in the influence areas of a hydroelectric power plant on the Madeira River in the Amazon Basin. Biodiversity Data Journal 6: e24375.
 * Fernández F., E. E. Palacio, W. P. Mackay, and E. S. MacKay. 1996. Introducción al estudio de las hormigas (Hymenoptera: Formicidae) de Colombia. Pp. 349-412 in: Andrade M. G., G. Amat García, and F. Fernández. (eds.) 1996. Insectos de Colombia. Estudios escogidos. Bogotá: Academia Colombiana de Ciencias Exactas, Físicas y Naturales, 541 pp
 * Fernández Triana J. L., J. L. Fontenla, E. Portuondo Ferrer, and J. A. Genaro. 2005. Especies de himenópteros registrados en el Parque Nacional La Bayamesa, Cuba, 17-22 de junio del 2003 y 2-10 de febrero del 2004. In Maceira F., D., A.Fong G., W. S. Alverson, y/and T. Wachter, eds. 2005. Cuba: Parque Nacional La Bayamesa. Rapid Biological Inventories Report 13. The Field Museum, Chicago.
 * Fernández, F. and S. Sendoya. 2004. Lista de las hormigas neotropicales. Biota Colombiana Volume 5, Number 1.
 * Fontanla Rizo J.L. 1997. Lista preliminar de las hormigas de Cuba. Cocuyo 6: 18-21.
 * Fontenla J. L., and J. Alfonso-Simonetti. 2018. Classification of Cuban ants (Hymenoptera: Formicidae) into functional groups. Poeyana Revista Cubana de Zoologia 506: 21-30.
 * Fontenla Rizo J. L. 1993. Mirmecofauna de Isla de la Juventud y de algunos cayos del archipielago cubano. Poeyana. Instituto de Ecologia y Sistematica, Academia de Ciencias de Cuba 444:1-7.
 * Fontenla Rizo J. L. 1997. Lista preliminar de las hormigas de Cuba (Hymenoptera: Formicidae). Cocuyo 6: 18-21.
 * Forel A. 1905. Miscellanea myrmécologiques II (1905). Ann. Soc. Entomol. Belg. 49: 155-185.
 * 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.
 * Gonthier, D. J., K. K. Ennis, S. M. Philpott, J. Vandermeer, and I. Perfecto. 2013. Ants defend coffee from berry borer colonization. BioControl 58: 815-820.
 * Gove, A. D., J. D. Majer, and V. Rico-Gray. 2009. Ant assemblages in isolated trees are more sensitive to species loss and replacement than their woodland counterparts. Basic and Applied Ecology 10: 187-195.
 * Guerrero R. J., and C. E. Sarmiento. 2010. Distribución altitudinal de hormigas (Hymenoptera, Formicidae) en la vertiente noroccidental de la Sierra Nevada de Santa Marta (Colombia). Acta Zoologica mexicana (n.s.) 26(2): 279-302.
 * INBio Collection (via Gbif)
 * Jaffe, K., et al. 2007. Comparing the ant fauna in a tropical and a temperat forest canopy. Ecotropicos 20(2):74-81
 * 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.
 * Longino J. T. 2013. Ants of Nicargua. Consulted on 18 Jan 2013. https://sites.google.com/site/longinollama/reports/ants-of-nicaragua
 * Longino J. et al. ADMAC project. Accessed on March 24th 2017 at https://sites.google.com/site/admacsite/
 * 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.
 * Mathis, K. A., S. M. Philpott, and S. R. Ramirez. 2016. Variation in spatial scale of competing polydomous twig-nesting ants in coffee agroecosystems. Insectes Sociaux 63: 447-456.
 * Menozzi C, Russo G. 1930. Contributo alla conoscenza della mirmecofauna della Repubblica Dominicana (Antille). Bollettino del Laboratorio di Zoologia Generale e Agraria della Reale Scuola Superiore d'Agricoltura. Portici. 24: 148-173.
 * Mirmecofauna de la reserva ecologica de San Felipe Bacalar
 * Moreau C. S., M. A. Deyrup, and L. R. David Jr. 2014. Ants of the Florida Keys: Species Accounts, Biogeography, and Conservation (Hymenoptera: Formicidae). J. Insect Sci. 14(295): DOI: 10.1093/jisesa/ieu157
 * Morrison L. W. 1998. A review of Bahamian ant (Hymenoptera: Formicidae) biogeography. Journal of Biogeography 25: 561-571.
 * Morrison, Lloyd. 2006. The Ants of Small Bahamian Cays. Bahamas Naturalist & Journal of Science. 1(2):27-32.
 * Pereira M. C., J. H. C. Delabie, Y. R. Suarez, and W. F. Antonialli Junior. 2013. Spatial connectivity of aquatic macrophytes and flood cycle influence species richness of an ant community of a Brazilian floodplain. Sociobiology 60(1): 41-49.
 * Perez-Sanchez A. J., J. E. Lattke, and A. L. Viloria. 2012. Patterns of Ant (Hymenoptera: Formicidae) Richness and Relative Abundance along an Aridity Gradient in Western Venezuela. Neotrop Entomol DOI 10.1007/s13744-012-0096-y
 * Philpott, S.M. and P.F. Foster. 2005. Nest-site limitation in coffee agroecosytems: Artificial nests maintain diversity of arboreal ants. Ecological Applications 15(4):1478-1485
 * Philpott, S.M., P. Bichier, R. Rice, and R. Greenberg. 2007. Field testing ecological and economic benefits of coffee certification programs. Conservation Biology 21: 975-985.
 * Portuondo E. F., and J. L. Reyes. 2002. Mirmecofauna de los macizos montañosos de Sierra Maestra y Nipe-Sagua-Baracoa. Cocuyo 12: 10-13
 * Portuondo E. F., and J. L. Reyes. 2006. Species of Hymenoptera recorded in the Reserva Ecológica Pico Mogote, Santiago de Cuba Province, 20-25 September 2002. In: Maceira F., D., A. Fong G., y/and W. S. Alverson, eds. 2006. Cuba: Pico Mogote. Rapid Biological Inventories Report 09. The Field Museum, Chicago.
 * Portuondo Ferrer, E. and J. Fernandez Triana. Biodiversidad del orden Hymenoptera en Los Macizos Montanosos de Cuba Oriental. Boletin S.E.A. 35:121-136.
 * Pérez-Sánchez A. J., J. E. Lattke, and M. A. Riera-Valera. 2014. The Myrmecofauna (Hymenoptera: Formicidae) of the Macanao Semi-arid Peninsula in Venezuela: An Altitudinal Variation Glance. J Biodivers Biopros Dev 1: 116. doi:10.4172/ijbbd.1000116
 * Ramos L. de S., R. Zanetti, C. G. S. Marinho, J. H. C. Delabie, M. N. Schlindwein, and R. P. Almado. 2004. Impact of mechanical and chemical weedings of Eucalyptus grandis undergrowth on an ant community (Hymenoptera: Formicidae). Rev. Árvore 28(1): 139-146.
 * Reyes, J. L. "Inventario de la colección de hormigas (Hymenoptera: Formicidae) del Centro Oriental de Ecosistemas y Biodiversidad, Santiago de Cuba, Cuba." Boletín de la Sociedad Aragonesa 36 (2005): 279-283.
 * Reynoso-Campos J. J., J. A. Rodriguez-Garza, and M. Vasquez-Bolanos. 2015. Hormigas (Hymenoptera: Formicidae) de la Isla Cozumel, Quintana Roo, Mexico (pp. 27-39). En: Castaño Meneses G., M. Vásquez-Bolaños, J. L. Navarrete-Heredia, G. A. Quiroz-Rocha e I. Alcalá-Martínez (Coords.). Avances de Formicidae de  México.  UNAM,  Universiad  de  Guadalajara, Guadalajara, Jalisco.
 * Rico-Gray, V. 1993. Use of plant-derived food resources by ants in the dry tropical lowlands of coastal Veracruz, Mexico. Biotropica 25(3):301-315.
 * Rico-Gray,V., J.G. Garcia-Franco, M. Palacios-Rios, C. Diaz-Castelazo, V. Parra-Tabla and J.A. Navarro. 1998. Geographical and Seasonal Variation in the Richness of Ant-Plant Interactions in Mexico. Biotropica 30(2):190-200.
 * Saarinen, E.V. and J.C. Daniels.2006. Miami blue butterfly larvae (Lepidoptera: Lycaenidae) and ants (Hymenoptera: Formicidae): New information on the symbionts of an endangered taxon. Florida Entomologist 89(1): 69-74
 * Torres, Juan A. and Roy R. Snelling. 1997. Biogeography of Puerto Rican ants: a non-equilibrium case?. Biodiversity and Conservation 6:1103-1121.
 * Vásquez-Bolaños M. 2011. Lista de especies de hormigas (Hymenoptera: Formicidae) para México. Dugesiana 18: 95-133
 * Ward P. S. 1985. The Nearctic species of the genus Pseudomyrmex (Hymenoptera: Formicidae). Quaestiones Entomologicae 21: 209-246
 * 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
 * Weber N. A. 1948. Studies on the fauna of Curaçao, Aruba, Bonaire and the Venezuelan islands: No. 14. Ants from the Leeward Group and some other Caribbean localities. Natuurwetenschappelijke Studiekring voor Suriname en de Nederlandse Antillen 5: 78-86.
 * Wetterer J. K. 2018. Native and exotic ants (Hymenoptera: Formicidae) nesting in red mangroves (Malpighiales: Rhizophora mangle) of eastern Florida. Transactions of the American Entomological Society, 144(2): 347-357.
 * Wheeler W. M. 1905. The ants of the Bahamas, with a list of the known West Indian species. Bulletin of the American Museum of Natural History 21: 79-135.
 * 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. 1908. The ants of Jamaica. Bulletin of the American Museum of Natural History 24: 159-163.
 * Wheeler W. M. 1913. The ants of Cuba. Bulletin of the Museum of Comparative Zoology 54: 477-505.
 * Wheeler W. M. 1917. Jamaican ants collected by Prof. C. T. Brues. Bulletin of the Museum of Comparative Zoology 61: 457-471.
 * Wheeler W. M. 1942. Studies of Neotropical ant-plants and their ants. Bulletin of the Museum of Comparative Zoology 90: 1-262.
 * Wheeler W. M., and I. W. Bailey. 1920. The feeding habits of pseudomyrmine and other ants. Transactions of the American Philosophical Society (2)22: 235-279.
 * Wheeler W. M., and W. M. Mann. 1914. The ants of Haiti. Bulletin of the American Museum of Natural History 33: 1-61.
 * Wheeler, William Morton. 1911. Additions to the Ant-Fauna of Jamaica. Bulletin American Museum of Natural History. 30:21-29.
 * 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.
 * da Silva Araujo, M., Castro Della Lucia, T.M., DA VEIGA, Clayton E y CARDOSO DO NASCIMENTO, Ivan. 2004. Efeito da queima da palhada de cana-de-açúcar sobre comunidade de formicídeos. Ecol. austral. 14(2): 191-200.
 * da Silva de Oliveira A. B., and F. A. Schmidt. 2019. Ant assemblages of Brazil nut trees Bertholletia excelsa in forest and pasture habitats in the Southwestern Brazilian Amazon. Biodiversity and Conservation 28(2): 329-344.