Stenamma chiricahua

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Stenamma chiricahua
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Stenammini
Genus: Stenamma
Species: S. chiricahua
Binomial name
Stenamma chiricahua
Snelling, R.R., 1973

Stenamma chiricahua casent0000297 profile 1.jpg

Stenamma chiricahua casent0000297 dorsal 1.jpg

Specimen labels

There is no information published about the biology of this species. The type specimens were collected from a shaded creek bed. Other collection records show they make nest chambers under stones, with one collection noted as occurring in a pine/fir/oak forest.


Snelling (1973) - Worker hardly distinguishable from that of Stenamma smithi but smaller, scape with decumbent hairs, propodeum above metapleural gland with distinct longitudinal rugulae and metanotal depression narrow, V-shaped. Female similar to that of S. smithi but disc of mesoscutum smooth, with scattered coarse pilgerous punctures, striae or rugulae absent.

The female of S. chiricahua appears readily separable from S. smithi and known females of other North American species by the smooth and shiny mesonotum, which wholly lacks longitudinal rugulae in the area between the parapsides, and the nonsculptured first sternite. The nonstriate mesoscutum is shared with the female of Stenamma punctatoventre, from which it differs most obviously by the smooth, shiny first sternite. The shiny mesonotum, long basal propodeal face and lack of propodeal spines are characteristic of the male.

Workers are brownish ferruginous, with yellowish legs and antennae that are more reddish.


Distribution based on Regional Taxon Lists

Nearctic Region: United States (type locality).

Distribution based on AntMaps


Distribution based on AntWeb specimens

Check data from AntWeb


USA. Arizona. Known from the Catalina, Chiricahua and Huachuca Mountains.



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

  • chiricahua. Stenamma chiricahua Snelling, R.R. 1973c: 7, figs. 6-11 (w.q.m.) U.S.A.



Measurements. HL 0.76-0.86; HW 0.65-0.73; SL 0.53-0.60; WL 0.90-1.03; PW 0.43-0.50.

Head. A little longer than broad, CI 80-87, longer than scape, sides almost parallel, nearly as broad above as below. Eyes of moderate size, with five to seven facets in greatest diameter, OMD 1.2-1.6 x EL; OI 13-17. Scape stout, a little shorter than HW, SI 80-85, cylindrical at bend, thickened near apex. Mandible with six or seven teeth, three apical teeth largest, median and second basal teeth reduced; shiny, longitudinally rugulose, breaking up into elongate punctures on blade. Median lobe of clypeus slightly produced beyond clypeal margin, longitudinally depressed and laterally carinulate, with transverse carinula at summit of declivity, thus appearing truncate in frontal view. Depressed frontal area and clypeus shiny; remainder of head slightly shiny, lightly punctulate between reticulate pattern of fine rugulae.

Thorax. Pronotal neck closely punctulate and slightly shiny; sides shinier, lightly punctulate between fine, irregular longitudinal rugulae; summit of declivity usually with several irregular transverse rugulae, sometimes only one; promesonotal dorsum moderately shiny, finely and sparsely punctulate between fine, longitudinal rugulae, punctulation coarser and closer on posterior third. Mesopleura densely punctate, usually with a few irregular longitudinal rugulae, slightly shiny. Metanotal depression, in profile, usually shallow, Vshaped. Propodeal sides shiny, finely punctulate, with several distinct longitudinal rugulae above opening of metapleural gland; basal face conspicuously longer than posterior face, with transverse welt anteriorly, surface moderately shiny and finely punctulate, often with a few fine transverse rugulae; spines sharp, short, separated by about twice their length; posterior face shiny, impunctate.

Petiole. Shape as in Stenamma smithi (Cole, 1966), nodes usually closely punctate and with a few rugulae, but may be largely impunctate and with rugulae obscure or absent.

Gaster. As in S. smithi but with longer striae (up to 0.13 mm) at base of first tergite.

Pilosity. Similar to S. smithi, but hairs of scape fully decumbent; erect cephalic hairs a little more numerous.

Color. Brownish ferruginous, legs yellowish, antennae more reddish.


Measurements. HL 0.77-0.88 (0.87); HW 0.65-0.77 (0.75); SL 0.57-0.63 (0.60); WL 1.07-1.27 (1.27); PW 0.60-0.70 (0.70).

Head. A little longer than broad, CI 85-89 (87), in frontal view sides slightly convergent above, occiput flat or slightly concave. Eyes large, OMD 0.54-0.64 (0.57) x EL; OI 25-28. Mandibles, clypeus and scape as described for worker. Sculpture as described for worker but rugulae coarser and reticulate pattern better defined.

Thorax. Declivitous face of pronotum shiny, sparsely punctulate and with several distinct transverse rugulae; sides shiny, sparsely punctulate and with distinct, through irregular, longitudinal regulae. Mesoscutum indistinctly transversely striatopunctate along anterior margin, disc smooth and shiny, without longitudinal rugulae or striae between parapsides, with scattered coarse piligerous punctures. Upper mesopleural plate with fine longitudinal striae, the lower plate largely smooth and shiny, except a few fine striae and punctures along posterior margin. Metapleura and sides of propodeum shiny, sparsely punctate and with strong longitudinal rugae. Scutellum coarsely rugulose at sides, more finely and sparsely rugulose in middle. Base of propodeum transversely rugulose and moderately shiny; declivity smooth, impunctate, shiny; basal and declivitous faces about equally long; spines moderately long, only a little shorter than distance between them.

Petiole, gaster, pilosity, color. As described for worker.

Wings. Forewing about 4.5 mm long, whitish, with pale brownish veins, venation of the brevicorne type, i.e., r-m absent, Mf3 present; first abscissa of Rs+M very short, about one-fourth as long as second abscissa.


Measurements. HL 0.57-0.62 (0.62); HW 0.50-0.53 (0.52); SL 0.25-0.27 (0.27); WL 1.17-133. (1.33); PW 0.63-0.73 (0.63).

Head. A little longer than broad, CI 83-89 (84). Scape short, straight, much shorter than HW, SI 47-53 (52). Eyes large and strongly convex, facets coarse, OI 43-45 (43), OMD reduced to a narrow transverse strip. Mandibles shiny, with three to five teeth. Median lobe of clypeus strongly convex, apically with a shallow longitudinal depression; apical margin slightly sinuate in middle. Ocelli small, hardly raised above surface, distance between posterior ocelli slightly greater than distance between either and anterior ocellus, the latter distance about 1.5 x diameter of anterior ocellus (about 0.07 mm). Mandibles, clypeus and frontal depression shiny, with a few fine, scattered punctures; remainder of front of head a little less shiny, superficially finely and closely punctulate, area between eyes and clypeus with a few fine, obscure rugulae; occipital area shiny, with a few fine scattered punctures; side of head moderately shiny, finely and closely punctulate.

Thorax. Shape very similar to that of S. brevicorne Mayr as figured by Creighton (1950), but mesonotum not as strongly depressed behind. Base of propodeum strongly sloping, flat or gently convex, about twice as long as posterior face; juncture of anterior and posterior faces angulate, neither spinose nor tuberculate. Mesonotum smooth and shiny, with a few fine piligerous punctures. Metanotum moderately shiny, finely and closely longitudinally striate, with fine punctulae between striae. Mesepisternum moderately shiny, finely longitudinally striate and weakly punctulate; or, striate and punctulate along margins only. Mesosternum mostly smooth and shiny, weakly punctulate. Metepisternum slightly shiny, densely punctulate. Propodeum densely punctulate and slightly shiny laterally, anterior and posterior faces mostly smooth and shiny.

Petiole. Dorsal face of anterior peduncle longer than anterior face of node, node low and rounded in profile. Node of postepetiole low in profile, apparently a little more convex than in S. brevicorne. Nodes smooth and shiny, remainder moderately shiny and closely punctulate.

Gaster, pilosity As described for Stenamma brevicorne (Smith, 1957).

Color. Brownish ferruginous, antennae and legs yellowish to yellowish brown. Wings whitish, with yellowish veins and stigma.

Wings. Length 3.7-3.9 mm, otherwise as described for female.

Type Material

Upper Cave Creek, 6000-7500', Chiricahua Mts., Cochise Co., Ariz., 15 August 1970 (V. Roth), in shaded creek bed.

Holotype, allotype, 4 male, 15 worker paratypes in LACM; two female, 10 male, 29 worker para types in WSC; one female, two male, three worker paratypes in AMNH; three paratypes (one each caste) in ACC, GCW, MCZ and USNM.

Holotype alate female, allotype male; 8 alate females, 10 males and 36 workers, paratypes (type series). Additional paratypes: dealate female, 11 males, 36 workers: Ramsey Canyon, Huachuca Mts., Cochise Co, Ariz., 25 August 1932 (W. S. Creighton: WSC).


Commemorative. After Chiricahua, Apache Indian tribe historically resident in southeastern Arizona.


  • Snelling, R. R. 1973c. Studies on California ants. 7. The genus Stenamma (Hymenoptera: Formicidae). Contr. Sci. (Los Angel.) 245: 1-38 (page 7, figs. 6-11 worker, queen, male described)

References based on Global Ant Biodiversity Informatics

  • Allred D. M. 1982. Ants of Utah. The Great Basin Naturalist 42: 415-511.
  • Allred, D.M. 1982. The ants of Utah. Great Basin Naturalist 42:415-511.
  • Cover S. P., and R. A. Johnson. 20011. Checklist of Arizona Ants. Downloaded on January 7th at
  • Johnson R. Personnal Database. Accessed on February 5th 2014 at
  • Snelling R. R. 1973. Studies on California ants. 7. The genus Stenamma (Hymenoptera: Formicidae). Contributions in Science (Los Angeles) 245: 1-38.