Stenamma ochrocnemis

Stenamma ochrocnemis is known mostly from extracts of sifted leaf litter collected from the forest floor, but workers also have been found at cookie baits and once underneath a rock. The species is a high-elevation specialist occurring from approximately 1600–2750 m, with most collections around 2000 m. It inhabits wet montane forests, such as cloud forest, oak forest, hardwood forest, and mixed oak cloud forest.

Identification
Branstetter (2013) - Integument mostly dark red-brown to orange-brown, with appendages a distinctly lighter, uniform yellow-brown; small- to medium-sized species (see HL, ML, PrW below); anterior clypeal margin undulating, usually with 4 sharp to blunt teeth, outer teeth often larger and sharper; basal margin of mandible usually sinuous, with a shallow to very deep basal depression, but without a basal tooth; gastral pilosity usually appearing somewhat dense, with setae subdecumbent to decumbent and not obviously bilayered, but sometimes more clearly bilayered, with subdecumbent setae becoming suberect; head completely sculptured, mostly rugoreticulate; mesosoma usually mostly sculptured with rugae and punctate, but pronotum sometimes with sculpture largely effaced; petiole of moderate length, somewhat robust; eye relatively small (EL 0.07–0.12, REL 12–17), subcircular to oval-shaped, with 4–6 ommatidia at greatest diameter; propodeal spines tuberculate (PSL 0.07–0.14, PSI 1.0–1.4). Similar species: Stenamma catracho, Stenamma manni. The most distinctive feature of this species is its light colored legs, which always make it stand out from other Stenamma species when sorting specimens in ethanol. Across its range there is significant variation in body size, surface sculpture, gastral pilosity and the configuration of the clypeus and basal margin of the mandible.

Distribution
Southern Mexico to Honduras.

Distribution based on Regional Taxon Lists
Neotropical Region: Guatemala, Honduras, Mexico.

Nomenclature
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 *  ochrocnemis. Stenamma ochrocnemis Branstetter, 2013: 207, figs. 134-137 (w.q.) HONDURAS.

Worker
(20 measured) HL 0.63–0.83 (0.71), HW 0.54–0.73 (0.60), FLD 0.14–0.20 (0.15), PCW 0.02–0.03 (0.02), SL 0.47–0.69 (0.55), EL 0.07–0.12 (0.08), ACL 0.48–0.66 (0.56), ML 0.76–1.09 (0.86), PrW 0.37–0.50 (0.41), PSL 0.07–0.14 (0.10), SDL 0.06–0.10 (0.08), PL 0.28–0.41 (0.33), PH 0.16–0.22 (0.18), PW 0.13-0.18 (0.14), PPL 0.14–0.21 (0.16), PPH 0.14–0.20 (0.16), PPW 0.16–0.22 (0.17), MFL 0.51–0.77 (0.60), MTL 0.43–0.63 (0.50), CI 83–88 (85), SI 82–95 (92), REL 12–17 (13), FLI 25–31 (26), PSI 1.0–1.4 (1.2), MFI 94–110 (100), ACI1 65–70 (69), ACI2 92–104 (101).

Small- to medium-sized species; general body color mostly dark red-brown (almost black) to orange-brown, with head and pronotum darker, and gaster with lighter patches of brown; appendages mostly a uniform and distinctly lighter orange-brown to yellow-brown; setae golden brown; mandible usually with 6–7 teeth (usually 6), but sometimes with 1–3 additional small denticles, middle 2–3 teeth nearest basal tooth often worn and indistinct; basal margin of mandible usually sinuous (rarely straight), with a shallow to very deep basal depression, but without a basal tooth; mandible mostly smooth and shining, with scattered piligerous punctae and striae (mostly on lateral side); anterior clypeal margin usually with 4 sharp to blunt teeth, outer teeth often larger and sharper, sometimes teeth reduced (especially inner two teeth), almost absent, and clypeal margin strongly emarginate; median clypeal lobe with a pair of very faint longitudinal carinulae, and a short transverse carinula near apex, remainder of clypeus smooth and shiny; posterior extension of the clypeus between the antennal insertions narrow (PCW 0.02–0.03), with sides subparallel; frontal lobes usually of moderate width, but somewhat expanded in Cusuco population (FLD 0.14–0.20, FLI 25–31); torular lobes not completely covered in full-face view; frontal carinae blending into head sculpture, not extending beyond about midpoint level of eye; head subrectangular to oval-shaped (CI 83–88), with posterior margin flat to slightly depressed medially; face mostly rugoreticulate, with a few longitudinal rugae along the midline, sometimes sculpture more polished and posterior quarter of head becoming smooth and shiny, interstices faintly punctate; scape of moderate length (SI 82–95), usually not reaching posterior margin in full-face view; scape surface mostly smooth and shiny, with scattered piligerous punctae; funiculus with a somewhat distinct 4-segmented antennal club (ACI2 65–70); pronotum sculpture varying from nearly completely smooth and shiny to strongly rugose (dorsum) and punctate or rugulose (side), with rugae mostly longitudinal in orientation; mesopleuron and propodeal side mostly punctate, with a few rugulae; propodeal dorsum and declivity (to a lesser degree) with punctae and transverse carinulae; promesonotum in profile low-domed, roughly symmetrical; location of promesonotal suture obscured to well-defined, depending on degree of pronotal sculpturing; metanotal grove well-demarcated, of moderate width and depth; propodeal spines tuberculate (PSL 0.07–0.14, PSI 1.0–1.4); petiole of average length (PL/HW 0.51–0.57); petiolar node of moderate to small size (PH/PL 0.53–0.62) and variable in shape, being either wedge shaped and strongly asymmetrical, or subconical, with the apex gently rounded and pointing only slightly posteriad; postpetiole in profile average-looking, about the same size as petiolar node (PPH/PH 0.83–0.96); anterior faces of petiolar nodes smooth and shiny, remaining surfaces of waist mostly punctate, with a few rugulae around nodes; gaster mostly smooth and shiny, with scattered piligerous punctate and a ring of short striae around the anterior constriction; most of body dorsum with somewhat short standing pilosity; scape decumbent to appressed; gastral pilosity variable, usually appearing somewhat dense, with setae subdecumbent to decumbent and not obviously bilayered, but sometimes more clearly bilayered, with subdecumbent setae becoming suberect; setae on legs decumbent to appressed, with suberect to subdecumbent setae on coxae and profemur venter.

Queen
(5 measured) HL 0.72–0.85 (0.75), HW 0.65–0.76 (0.67), FLD 0.17–0.21 (0.17), PCW 0.03–0.05 (0.05), SL 0.53–0.66 (0.59), EL 0.17–0.20 (0.17), ACL 0.55–0.62 (0.57), ML 1.01–1.26 (1.06), PrW 0.55–0.73 (0.57), PSL 0.13–0.17 (0.15), SDL 0.08–0.12 (0.10), PL 0.37–0.48 (0.39), PH 0.20–0.25 (0.21), PW 0.17–0.22 (0.18), PPL 0.18–0.22 (0.19), PPH 0.19–0.26 (0.20), PPW 0.21–0.29 (0.22), MFL 0.60–0.80 (0.65), MTL 0.53–0.69 (0.56), CI 88–90 (90), SI 82–89 (88), REL 25–28 (25), FLI 26––28 (26), PSI 1.5–1.7 (1.5), MFI 95–107 (103), ACI1 64–68 (67), ACI2 93–106 (96).

Same as worker except for standard queen modifications and as follows: pronotum transversely rugose laterad, becoming smooth mesad; mesoscutum ranging from mostly smooth, with some faint foveolae, to mostly carinulate/rugose (strength of sculpture correlates with pronotum sculpture of worker); scutellum longitudinally rugose, often with a central patch of smooth cuticle; most of katepisternum and sometimes lower half of anepisternum smooth; propodeal spines slightly more developed; setae on mesoscutum subdecumbent to appressed, more dense; pilosity in general slightly more dense; wing venation in Figure 135D.

Type Material
Holotype worker. HONDURAS, Comayagua: 10km ENE Comayagua, 14.45982°N, 87.54564°W ±20m, 2000m, 15 May 2010, cloud forest, ex sifted leaf litter (LLAMA, collection Wa-C-03-1-11) USNM, specimen CASENT0621468. Paratypes: same data as holotype but 14.45980°N, 87.54573°W ±20m, 2000m, 15 May 2010 (LLAMA, Wa-C-03-1-09) 1dq, 1w, USNM, CASENT0621449, CASENT0621450, 1w, CAS, CASENT0621451]; 14.45994°N, 87.54523°W ±20m, 2000m, 15 May 2010 (LLAMA, Wa-C-03-1-21) 1dq, 1w, EAPZ, CASENT0621501, CASENT0621502, 1w, ECOSCE, CASENT0621503, 1w, FMNH, CASENT0623437, 1w, ICN, CASENT0623438, 1w, INBio, CASENT0623439, 1w, JTLC, CASENT0623440, 1w, LACM, CASENT0623442, 1dq, 1w, MGBPC, CASENT0623441 CASENT0623443; 14.46032°N, 87.54512 ±20m, 2000m, 15 May 2010 (LLAMA, Wa-C-03-1-30) 1w, MCZ, CASENT0623444, 1w, MZSP, CASENT0623445, 1w, UCDC, CASENT0623446, 1w, UNAM, CASENT0623447, 1w, UVGC, CASENT0623448.

Etymology
The specific epithet ochrocnemis is derived from the greek words ochro- and cnemis and means light-colored legs, which is a distinctive feature of the species.

References based on Global Ant Biodiversity Informatics

 * Branstetter M.G. 2013. Revision of the Middle American clade of the ant genus Stenamma Westwood (Hymenoptera, Formicidae, Myrmicinae). ZooKeys 295: 1277
 * Dattilo W. et al. 2019. MEXICO ANTS: incidence and abundance along the Nearctic-Neotropical interface. Ecology https://doi.org/10.1002/ecy.2944
 * Longino J. T. L., and M. G. Branstetter. 2018. The truncated bell: an enigmatic but pervasive elevational diversity pattern in Middle American ants. Ecography 41: 1-12.