Pseudomyrmex subtilissimus

AntWiki - Where Ant Biologists Share Their Knowledge
Jump to navigation Jump to search
Pseudomyrmex subtilissimus
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Pseudomyrmecinae
Genus: Pseudomyrmex
Species: P. subtilissimus
Binomial name
Pseudomyrmex subtilissimus
(Emery, 1890)

Pseudomyrmex subtilissimus casent0902919 p 1 high.jpg

Pseudomyrmex subtilissimus casent0902919 d 1 high.jpg

Specimen Labels


A moderately elongate head (broader than Pseudomyrmex tenuissimus, more elongate than Pseudomyrmex spiculus and Pseudomyrmex villosus), short petiole, and light brown color (with banded gaster) characterize P. subtilissimus (Ward 1989).

Distinguishable from all other acacia-associated Pseudomyrmex by its small size (HW < 0.60), elongate head (CI < 0.66), apedunculate petiole, and scarcity of standing pilosity (Ward 1993).


Costa Rica and Nicaragua.

Distribution based on Regional Taxon Lists

Neotropical Region: Colombia, Costa Rica (type locality), Mexico, Nicaragua.

Distribution based on AntMaps


Distribution based on AntWeb specimens

Check data from AntWeb


Ward (1989) - This species has been collected only in, or on, swollen-thorn acacias, in association with Pseudomyrmex flavicornis (F. Smith). The collection records suggest that it is an obligate, non-aggressive acacia ant which somehow manages to coexist with P. flavicornis.



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

  • subtilissimus. Pseudomyrma subtilissima Emery, 1890b: 65, pl. 6, fig. 7 (w.q.) COSTA RICA. [Also described as new by Emery, 1894k: 53.] Combination in Pseudomyrmex: Kempf, 1972a: 224. See also: Ward, 1989: 432; Ward, 1993: 161.

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



measurements (n=17, except for FI where n=16). - HL 0.86-0.95, HW 0.55-0.59, MFC 0.020-0.032, CI 0.60-0.65, OI 0.52-0.59, REL 0.49-0.54, REL2 0.80-0.87, OOI 0.38-0.89, VI 0.79-0.88, FCI 0.035-0.055, SI 0.41-0.47, SI2 0.50-0.57, FI 0.44-0.53, POI 1.60-1.88, MPI 0.015-0.039, NI 0.52-0.66, PLI 0.65-0.75, PWI 0.56-0.68, PPWI 1.18-1.35.

diagnosis. - Similar to Pseudomyrmex spiculus (q.v.) except as follows: smaller, head more elongate (HW 0.55-0.59, CI 0.60-0.65), eyes shorter, not reaching the level of the median ocellus (REL 0.49-0.54); basal face of propodeum flatter, meeting the decIivitous face at a more distinct angle; petiole shorter, higher (PLI 0.65-0.75). Most of body uniformly light brown; gaster dark brown, with contrasting light brown band on anterior half of abdominal tergite IV.

Type Material

Syntype workers, one dealate queen, Alajuela, Costa Rica (Alfaro) (Museo Civico di Storia Naturale, Genoa) [Examined]. One syntype worker here designated as LECTOTYPE.


  • Emery, C. 1890b. Voyage de M. E. Simon au Venezuela (Décembre 1887 - Avril 1888). Formicides. Ann. Soc. Entomol. Fr. (6)(10): 55-76 (page 65, pl. 6, fig. 7 worker, queen described)
  • Emery, C. 1894l. Estudios sobre las hormigas de Costa Rica. An. Mus. Nac. Costa Rica 1888- 1889: 45-64 (page 53, also described as new)
  • Kempf, W. W. 1972b. Catálogo abreviado das formigas da regia~o Neotropical. Stud. Entomol. 15: 3-344 (page 224, Combination in Pseudomyrmex)
  • Ward, P. S. 1989a. Systematic studies on pseudomyrmecine ants: revision of the Pseudomyrmex oculatus and P. subtilissimus species groups, with taxonomic comments on other species. Quaest. Entomol. 25: 393-468 (page 432, see also)
  • Ward, P. S. 1993. Systematic studies on Pseudomyrmex acacia-ants (Hymenoptera: Formicidae: Pseudomyrmecinae). J. Hym. Res. 2: 117-168 (page 161, see also)