Megalomyrmex nocarina

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Megalomyrmex nocarina
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Solenopsidini
Genus: Megalomyrmex
Species group: silvestrii
Species: M. nocarina
Binomial name
Megalomyrmex nocarina
Longino, 2010

Megalomyrmex nocarina casent0629677 p 1 high.jpg

Megalomyrmex nocarina casent0629677 d 1 high.jpg

Specimen Labels

Megalomyrmex nocarina occurs in mature wet forest habitats of the Atlantic slope of Costa Rica. It occurs from near sea level to 1110 m elevation. It is known exclusively as isolated workers in Winkler samples of forest floor litter. The nesting and feeding habits of nocarina remain to be discovered, but the similarity to Megalomyrmex mondabora and Megalomyrmex mondaboroides suggest that nocarina, too, might be a specialized predator or social parasite of Attini. (Longino 2010)


Boudinot et al. (2013) - Worker Uniquely identifiable among Central American Megalomyrmex by the following combination of characters: (1) mandible with 7–10 minute denticles subtending two large apical teeth; (2) katepisternum smooth and shining; (3) occipital carina visible in full-face view; (4) foraminal carina usually absent; (5) postpetiole extremely robust, weakly compressed anteroposteriorly; (6) postpetiolar sternum bulging, minutely dentate anteriorly.

Specimens from Panama have a foraminal carina, contradicting the namesake diagnostic character state. The species is additionally separated from other species in the mondabora complex by its long, thin, posterior clypeal portion.

Longino (2010) - This species is very easy to confuse with Megalomyrmex mondabora and Megalomyrmex mondaboroides, but the lack of a strong foraminal carina is reliably diagnostic. Also, the basal mandibular teeth are slightly larger and fewer in number.

Keys including this Species


sea-level to 1200 m

Latitudinal Distribution Pattern

Latitudinal Range: 10.98333333° to -3.083333°.

Tropical South

Distribution based on Regional Taxon Lists

Neotropical Region: Costa Rica (type locality), Panama.

Distribution based on AntMaps


Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.




Megalomyrmex nocarina inb0003678142 h 1 high.jpgMegalomyrmex nocarina inb0003678142 h 2 high.jpgMegalomyrmex nocarina inb0003678142 p 1 high.jpgMegalomyrmex nocarina inb0003678142 d 1 high.jpgMegalomyrmex nocarina inb0003678142 l 1 high.jpg


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

  • nocarina. Megalomyrmex nocarina Longino, 2010: 51, figs. 5A, 5C, 10A, 10B (w.) COSTA RICA.
    • Type-material: holotype worker, 12 paratype workers.
    • Type-locality: holotype Costa Rica: Heredia, Est. Biol. La Selva, 10°26’N, 83°59’W, 40-125 m., 16.ix.2005, TEAM AMI-1-W-044-03; paratypes: 1 worker with same data but 4.ix.2007, TEAM AMI-1-W-091-04, 1 worker with same data but, TEAM AMI-1-W-080-04, 1 worker 7 km. SW Pto Viejo, 10°24’14’’N, 84°02’22’’W, 160 m., 20.i.2006, TEAM AMI-2-W-059-03, 1 worker as last but 24.x.2006, TEAM AMI-2-W-105-06, 2 workers as last but 23.iv.2007, TEAM AMI-2-W-131-10, 1 worker 16 km. SSW Pto Viejo, 10°19’03’’N, 84°02’56’’W, 500 m., 16.x.2006, TEAM AMI-3-W-100-19, 5 workers Cantarrana, 11 km. ESE La Virgen, 10°20’43’’N, 84°03’28’’W, 300 m., 26.ii.2007, TEAM AMI-4-W-123-09.
    • Type-depositories: MCZC (holotype); CASC, INBC, LACM, MCZC, MZSP, UCDC, USNM (paratypes).
    • Status as species: Boudinot, et al. 2013: 56.
    • Distribution: Costa Rica, Panama.

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



(holotype): HW 0.701, HL 0.830, SL 0.822, EL 0.234, ML 1.217, CI 84, SI 99.

(n=9): HW 0.662–0.706, HL 0.799–0.859, SL 0.786–0.876, EL 0.222–0.259, ML 1.159–1.253, CI 82–85, SI 98–102.

Palp formula 3,2; mandible with large apical and subapical teeth, 7–9 smaller basal teeth of uniform size and spacing; dorsal surface of mandible smooth and shiny; clypeus convex, bulging medially but not obscuring anterior clypeal margin in full-face view; anterior clypeal margin projecting and somewhat angular; occipital carina forming a distinct rim visible in full-face view, anterior ends extending a short distance onto ventral surface of head, not much beyond level of foramen; face, clypeus, and ventral surface of head smooth and shiny, piligerous puncta very small, resulting in overall smooth and highly polished appearance; mesosoma smooth and shiny throughout, with a few short, coarse carinae on posterior margin of katepisternum, a few longitudinal carinae over metapleural gland; foraminal carina absent, dorsal metapleural lobe curves slightly onto posterior face of propodeum but ends abruptly; petiole and postpetiole smooth and shining; ventral margin of petiole flat, with a low transverse flange anteriorly that forms a blunt tooth in lateral view, a few faint transverse costulae variably present immediately posterior to anterventral tooth; ventral margin of postpetiole with a thin transverse costa anteriorly, a shallowly convex lobe, and 2–3 transverse costulae posteriorly; gaster smooth and shining; all dorsal body surfaces and appendages with abundant flexuous setae; color dark red brown.

Boudinot et al. (2013) - (n=7, plus 9 from Longino 2010): HW 0.66–0.72, HL 0.80–0.88, SL 0.78–0.90, OMD 0.09–0.11, EL 0.22–0.27, ML 1.16–1.34, CI 81–85, SI 97–103, EI 34–38, OMI 34–45.

Type Material

Holotype worker. COSTA RICA, Heredia: Estación Biológica La Selva, 10°26'N 83°59'W, 40–125 m, 16 Sep 2005 (Proyecto TEAM AMI–1–W–044–03) Museum of Comparative Zoology, unique specimen identifier INB0003678142]. Paratypes: Same data as holotype, except 4 Sep 2007 (Proyecto TEAM AMI–1–W–091–04), 1 worker California Academy of Sciences, INB0003695485; 12 Jun 2006 (Proyecto TEAM AMI–1–W–080–04), 1 worker Instituto Nacional de Biodiversidad, INB0003694200; 7 km SW Pto. Viejo, 10°24'14"N, 084°02'22"W, 160 m, 20 Jan 2006 (Proyecto TEAM AMI–2–W–059–03), 1 worker Los Angeles County Museum of Natural History, INB0003680680; same except 24 Oct 2006 (Proyecto TEAM AMI–2–W–105–06), 1 worker National Museum of Natural History, INB0003697094; same except 23 Apr 2007 (Proyecto TEAM AMI–2–W–131–10), 2 workers University of California, Davis, CASENT0613301; Instituto Nacional de Biodiversidad, INB0003699639; 16 km SSW Pto. Viejo, 10°19'03"N, 084°02'56"W, 500 m, 16 Oct 2006 (Proyecto TEAM AMI–3–W–100–09), 1 worker MCZ, INB0003696577; Cantarrana, 11 km ESE La Virgen, 10°20'43"N, 084°03'28"W, 300 m, 26 Feb 2007 (Proyecto TEAM AMI–4–W–123–09), 5 workers CAS, CASENT0613296; LACM, CASENT0613297; MCZ, CASENT0613298; USNM, CASENT0613299; Museu de Zoologia da Universidade de Sao Paulo, CASENT0613300; INBC, INB0003646495.


The name of this species refers to the lack of a foraminal carina. It is a noun in apposition and invariant.


References based on Global Ant Biodiversity Informatics

  • Boudinot B. E., T. P. Sumnicht, and R. M. M. Adams. 2013. Central American ants of the genus Megalomyrmex Forel (Hymenoptera: Formicidae): six new species and keys to workers and males. Zootaxa 3732(1): 1-82.
  • Longino J. T. 2010. A taxonomic review of the ant genus Megalomyrmex Forel (Hymenoptera: Formicidae) in Central America. Zootaxa 2720: 35-58
  • 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.