Carebara urichi

Individuals and nest series have been collected from the leaf-litter using Winkler sifting.

Identification
Fischer et al. (2014) - Antennae with eleven segments. Major worker: Head almost as long as wide to slightly longer, nearly subquadrate in full-face view, posterolateral corners rounded. Head with longitudinal striations, rugulae on the posterior side, propodeal spines absent or inconspicuous, petiolar ventral process large, digitiform and anteriorly directed, gaster covered by very abundant erect hairs. Minor worker: Head subrectangular, sides convex, posterior margin almost straight, posterolateral corners angulate, frons medially smooth and shiny, face with longitudinal rugulae and reticulations, propodeal spines short, acute-triangular and upwardly directed, metatibia with long, suberect hairs along outer edge, petiole anteroventrally with small, anteriorly-pointing tooth, gaster with relatively abundant, long, suberect or subdecumbent hairs.

Carebara urichi can be confused with Carebara brevipilosa, but is easily separated by the sculpture on the dorsal promesonotum, which is irregularly longitudinally rugose to rugoreticulate with few irregular longitudinal rugae in C. urichi minor workers and weakly to superficially reticulate or with few very short rugulae in C. brevipilosa. Carebara urichi and C. brevipilosa are the only two species in the C. polita group recorded for the Neotropical Region.

Distribution
This species is widely distributed in the neotropics, from México to Argentina.

Distribution based on Regional Taxon Lists
Neotropical Region: Belize, Brazil, Colombia, Costa Rica, Ecuador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Peru, Suriname, Trinidad and Tobago, Venezuela.

Habitat
Mainly found in rainforest and cloud forest at elevations ranging from 20–1470 m.

Biology
Wheeler (1937) reported: "This minute ant was previously known only from the type specimens collected in nests of the Guacharos (Steatornis), in a cave in Trinidad. Very recently Prof. A. S. Pearse has sent me two specimens which he found on bat guano in a cave in Yucatan. Its occurrence in leaf-mold in Cuba is not surprising since other minute cave-insects are known to live occasionally in similar situations, but we should expect it to be more abundant in some of the many bat-infested caves of the island."

Mann (1926) noted a colony of this ant, reported under the synonymized name Erebomyrma nevermanni, was collected in a rotten log (Reventazon, Santa Clara, Costa Rica) "in company with Pseudoponera stigma."

Castes
Borgmeier (1949) described and illustrated a case of “dinergatogyny” from a Costa Rican specimen of O. morai.

Worker
Major

Nomenclature

 *  urichi. Spelaeomyrmex urichi Wheeler, W.M. 1922c: 45, fig. 1 (w.) TRINIDAD. Fernández, 2004a: 206 (s.q.m.). Combination in Erebomyrma: Wilson, 1962a: 63; Wilson, 1986b: 61; in Oligomyrmex: Ettershank, 1966: 124; Bolton, 1995b: 300; in Carebara: Fernández, 2004a: 205. Senior synonym of eidmanni, morai, nevermanni: Fernández, 2004a: 205.
 * nevermanni. Erebomyrma nevermanni Mann, 1926: 103 (w.) COSTA RICA. Combination in Oligomyrmex: Ettershank, 1966: 124; in Erebomyrma: Wilson, 1986b: 61; in Oligomyrmex: Bolton, 1995b: 299. Junior synonym of urichi: Fernández, 2004a: 205.
 * morai. Erebomyrma morai Menozzi, 1931b: 271, fig. 7 (w.) COSTA RICA. Combination in Oligomyrmex: Ettershank, 1966: 124; in Erebomyrma: Brandão, 1991: 343; in Oligomyrmex: Bolton, 1995b: 299. Junior synonym of urichi: Fernández, 2004a: 205.
 * eidmanni. Erebomyrma eidmanni Eidmann, 1936: 47 (attributed to Menozzi) (s.w.q.) BRAZIL. Combination in Oligomyrmex: Ettershank, 1966: 123; in Erebomyrma: Wilson, 1986b: 61; in Oligomyrmex: Bolton, 1995b: 299. Junior synonym of urichi: Fernández, 2004a: 205.

Worker
Fischer et al. (2014) - Major (n=4): HW 0.97–0.99 (0.98), HL 1.01–1.06 (1.04), SL 0.41–0.44 (0.43), MDL 0.53–0.54 (0.53), EL 0.08, WL 0.97–1.02 (0.99), PNH 0.53–0.57 (0.54), PNW 0.56–0.61 (0.58), MNH 0.64–0.68 (0.66), PDH 0.42–0.46 (0.45), PTL 0.42–0.46 (0.44), PPL 0.25–0.26 (0.26), PTH 0.35–0.38 (0.37), PPH 0.26–0.30 (0.28), PTW 0.31–0.35 (0.33), PPW 0.38–0.43 (0.41), PSL 0.11–0.14 (0.13), MFL 0.58–0.61 (0.60), MTL 0.44–0.46 (0.45), CI 93–95 (94), SI 43–44 (44), MDI 54–55 (55), EI 8–9 (8), FI 60–62 (61), PSLI 12–14 (13), LPpI 88–96 (91), DPpI 152–167 (161), PpWI 124–132 (127), PpLI 57–60 (58), PpHI 74–80 (77).

Head slightly longer than wide (CI 93–95), in full-face view nearly subquadrate. Posterior margin of head with deep, V-shaped emargination, posterolateral corners rounded, sides subparallel and almost straight. Mandibles with five teeth. Anterior margin of clypeus nearly straight, sides convex. Frontal carinae absent to inconspicuous. Antenna with eleven segments, scapes short and reaching to about midlength of head (SI 43–44). Eyes present, multi-faceted, and comparatively large (EI 8–9).

In profile, promesonotum queen-like with moderately high pronotum, comparatively long scutum, and short scutellum, the latter slightly to strongly raised above convex to weakly convex dorsal outline of mesosoma. Promesonotal suture on dorsum present as broad impression, metanotum small and obliquely raised posteriorly. Propodeum higher than long in profile, with dorsal face oblique, declining posteriorly, propodeal spines and posterolateral lamella absent to reduced to slightly raised, posterior corners bluntly angulate, posterior declivity subvertical with well-developed lobe. Propodeal spiracle roundly convex and situated closer to dorsum of propodeum than to its center, not close to posterior declivity.

Petiole with relatively short peduncle, anteroventrally concave, with very conspicuous, short to relatively long, finger-like anterior process, posteroventrally convex, petiole node high, anteriorly oblique to weakly concave, posteriorly vertical and weakly concave, dorsum straight with a rounded angle anteriorly and a sharp right angle posteriorly. Postpetiole in profile squarish with rounded corners and lower than petiole (PpHI 74-80), with shallow, anteriorly angulate ventral process, anterior face almost vertical, dorsum almost straight and posterior face short and oblique. In dorsal view, petiole node much wider than long and anteroposteriorly flattened, anteriorly slightly convex, posterioly transverse and sharply marginate, postpetiole with wide, lamellate processes extending lateroventrally (PpWI 124-132), the node itself narrower than petiole and slightly wider than long, with convex sides, and anterior and posterior margins almost transverse.

Mandibles smooth and shiny, laterally weakly striate and with scattered punctures. Clypeus smooth and shiny, with several weak lateral carinae. Sculpture on frons and anterior sides of head with strong, irregular rugae, posterior parts of face coarsely rugoreticulate, interspaces weakly to superficially punctate, ventral side of head with long, parallel, longitudinal rugae. Mesosoma mostly coarsely and very irregularly rugoreticulate with punctate ground sculpture, rugoreticulate sculpture can be reduced on lateral surfaces, anepisternum sometimes with smooth and shiny area posteriorly. Petiole node and postpetiole dorsally smooth and shiny to faintly punctate, gaster shagreened or superficially punctate. Head and body usually with abundant, erect to suberect hairs of varying length and shorter decumbent to suberect pilosity, scapes and tibiae with appressed to decumbent pilosity and long suberect to erect hairs along outer edge. Color reddish brown, appendages and gaster light brown.

Minor (n=5): HW 0.36–0.44 (0.40), HL 0.41–0.51 (0.46), SL 0.29–0.34 (0.32), MDL 0.23–0.29 (0.26), EL 0.02, WL 0.45–0.59 (0.53), PNH 0.17–0.22 (0.19), PNW 0.23–0.27 (0.25), MNH 0.25–0.31 (0.28), PDH 0.17–0.22 (0.19), PTL 0.15–0.18 (0.16), PPL 0.11–0.12 (0.11), PTH 0.09–0.11 (0.10), PPH 0.08–0.09 (0.08), PTW 0.07–0.08 (0.08), PPW 0.08–0.10 (0.09), PSL 0.07–0.08 (0.07), MFL 0.30–0.39 (0.34), MTL 0.26–0.32 (0.29), CI 86–88 (87), SI 76–91 (81), MDI 62–66 (65), EI 4–6 (5), FI 80–91 (84), PSLI 17–19 (18), LPpI 139–160 (147), DPpI 69–81 (75), PpWI 109–122 (115), PpLI 67–80 (71), PpHI 71–83 (77).

Head almost as wide as long (CI 93–95), posterior margin nearly straight to weakly concave, sides convex. Mandible with four well-defined teeth, apical and preapical tooth larger than others. Anterior margin of clypeus very weakly concave, at each side with a triangular tooth. Frontal carinae moderately long, sometimes reaching posterior third of head. Antenna with eleven segments, scape short and reaching about 6/7 towards posterior margin of head (SI 76–91). Eyes consisting of one ommatidium (EI 4–6).

In profile, dorsum of promesonotum weakly convex, anteriorly sharply marginate and right-angled, posteriorly curving slightly downwards toward widely, but shallowly impressed metanotal groove. Dorsum of propodeum convex, softly declining posteriorly and slightly shorter than posterior declivity, anterodorsal corner convex, propodeal spines relatively short, acute (PSLI 14–15) and lamellate, lamella proceeding ventrally, ending in large propodeal lobes. Propodeal spiracle rounded and situated close to base of spines.

Petiole in profile with peduncle about as long as petiole node, anteroventrally concave, with small, acute, anteriorly pointing ventral process, posteroventrally weakly convex, petiole node low and dorsally rounded. Postpetiole in profile dorsally convex, ventrally almost straight, on average 1.5 times longer than high (LPpI 139–160), lower than petiole (PpHI 71–83). In dorsal view, petiole node almost as wide as long, anteriorly roundly convex, posteriorly nearly straight or weakly convex, postpetiole longer than wide (DPpI 69–81), slightly wider than petiole (PpWI 109–122), anteriorly tapering and posteriorly weakly concave. Gaster slender in dorsal view, its anterior margin straight to faintly convex.

Mandibles, clypeus and center of frons smooth and shiny, remainder of face coarsely rugoreticulate, with scattered punctures. Promesonotum dorsally with several irregular longitudinal rugae, interspaces superficially punctate to smooth, remainder of mesosoma alveolate, alveolae on basal lateropronotum sometimes strongly effaced. Gaster and dorsum of petiole and postpetiole smooth and shiny, remainder of waist segments weakly alveolate.

Head and body with long, suberect to erect hairs and shorter subdecumbent to decumbent pilosity. Scapes and tibiae with decumbent to subdecumbent pilosity, the latter with longer suberect hairs along outer edge. Color orange to dark orange with lighter colored antennae, legs and gaster.

Queen
Fernández (2004) - (n=2): HW 1.17-1.18; HL 1.15-1.25; SL 0.51-0.56; EL 0.24-0.25; WL 1.69-1.75; GL 1.93; TL 6.02-6.06; CI 95-100; SI 44-47.

General habitus as soldier with several differences: Posterior border of head slightly concave. Mandible with 5 tooth, with a space between subapical and remainder. Eyes big, bulging. Three ocellae present. Mesosoma modified as in myrmicine queens. Metanotum sharply defined. Propodeum armed with triangular teeth. Propodeal spiracle big, round, backward. Subpetiolar process well-defined. Sculpture and general pilosity as soldier.

Male
Fernández (2004) - HW 0.78; HL 0.63; SL 0.14; EL 0.34; WL 1.33; GL 1.17; TL 3.81; CI 124; SI 18.

Head subsphaerical. Eyes large. Mandibles narrow, not touching when closed, with two teeth, the apical twice as big as basal. Clypeus medially bulging. Ocellae turreted, the frontal round and prominent. Mesosternum bulging. Propodeum unarmed. Petiole larger that postpetiole, their peduncle running evenly in the dorsal face of node. Petiole ventrally without subpetiolar process, and with several irregular longitudinal carinae. Postpetiole low, broadly attached to the gaster. Genitalia strongly protruding, with aedeagus and parameres long and narrow. Body smooth and shining. Posterior half of head with transverse striation, anterior half more or less longitudinal striate. Most of promesonotum striatopunctate. Mesosoma punctate. Body dark brown, appendanges lighter. Wings dark.

Type Material
Fischer et al. (2014) - Spelaeomyrmex urichi W.M. Wheeler, 1922b: 9. Syntypes (11 minor workers) TRINIDAD: “Guacharo Cave” (F.M. Urich) [not examined].