Carebara bara

A Madagascar endemic, Carebara bara primarily inhabits arid habitats. Individuals and nest series have been collected from rotten logs, leaf litter, leaf mold, and rotten wood.

Identification
Azorsa and Fisher (2018) - Antennae ten-segmented. Major: Head nearly rectangular, longer than wide, head longitudinally rugose laterally, weakly reticulate near posterior margin of head, frons smooth and shiny, posterior margin of head medially concave, posterolateral corners rounded; posterodorsal corner of propodeum angulate, never with a pair of triangular teeth; dorsum of propodeum nearly flat; combined outline of dorsal surface of peduncle and anterior face of node nearly straight, dorsum rounded; gaster with sparse, long subdecumbent hairs and abundant, short decumbent hairs. Minor: Head longer than wide; posterodorsal corners of propodeum each armed with a weakly developed angular tooth, dorsum of propodeum slightly convex and declining posteriorly; combined outline of dorsal surface of peduncle and anterior face of node nearly straight, posterior margin convex, dorsum rounded; gaster covered by abundant decumbent to subdecumbent hairs, and with sparse and slightly longer subdecumbent hairs.

C. bara have three intermediates in the major worker subcaste with only minor variations between them. The shape of the posterolateral corner of the head and the posterior margin of the head do not vary much. Intermediate 3 has an increase in the size of the eyes, but only one ommatidium. Ocelli are absent in intermediates 1 and 2, and sometimes present in intermediate 3 (one ocellus). Intermediate 3 has reduced flight sclerites. In addition, the dorsum of the mesosoma of intermediate 3 is anteriorly convex and gradually slopes to a declivity. By comparison, in intermediates 1 and 2 the dorsum of the mesosoma is anteriorly convex, and the propodeum is below the promesonotum, which is flat and declining posteriorly to a declivity. Pilosity is nearly identical in all intermediates. The longitudinal rugae of the head are more finely marked in intermediate 1. The sculpture of the mesosoma, petiole and postpetiole is nearly identical in all the intermediates.

Carebara bara can be confused with Carebara berivelo but can be separated by the form of the propodeum. C. berivelo is armed with a pair of small triangular teeth while C. bara is unarmed in major workers and armed with a small angulate tooth in minor workers. This species can also be confused with Carebara tana, but in C. tana the combined outline of dorsal surface of peduncle and anterior face of node is medially concave. C. bara is widespread throughout most of Madagascar, with only one record in the center of the island and no records in the east, while C. berivelo and C. tana are restricted to the north of Madagascar. These three species occur in sympatry in the north of Madagascar, other four species were recorded at the same localities: Carebara grandidieri, Carebara kabosy, Carebara malagasy, and Carebara salegi, which can be separated from C. bara by the characters described above.

Distribution
Azorsa and Fisher (2018) - an endemic and widespread species, found across Madagascar, mainly in the tropical dry forest in western Madagascar and the desert spiny bush thicket in the southwest. In the center of Madagascar (montane forest) there is only one record. C. bara occurs in the dry forest, gallery forest, littoral rainforest, montane rainforest, spiny forest/dry forest transition, spiny forest/thicket, spiny thicket, spiny thicket gallery forest transition, and tropical dry forest, and has been collected at elevations ranging from 10–1410 m.

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Nomenclature

 *  bara. Carebara bara Azorsa & Fisher, 2018: 31, figs. 31, 32, 68 (w.) MADAGASCAR.

Worker
Major. (n=25): HL 0.54–0.71 (0.64); HW 0.41–0.56 (0.49); SL 0.21–0.27 (0.25); ML 0.11–0.18 (0.15); EL 0.01–0.03 (0.03); EM 0.15–0.21 (0.18); HD 0.28–0.40 (0.36); WL 0.46–0.65 (0.56); PSL 0.04–0.07 (0.05); PW 0.28–0.40 (0.33); MFL 0.25–0.36 (0.30); MFW 0.07–0.09 (0.08), MTL 0.15–0.29 (0.23); PTL 0.15–0.24 (0.23); PNL 0.08–0.11 (0.11); PTH 0.14–0.20 (0.16); PTW 0.12–0.17 (0.15); PPL 0.11–0.16 (0.13); PPNL 0.09–0.14 (0.12); PPH 0.11–0.17 (0.14); PPW 0.16–0.23 (0.19); GL 0.44–0.77 (0.59); GW 0.34–0.63 (0.40); CI 71–79 (77); MI 20–26 (23); SI 34–43 (39); MLI 57–65 (61); PPLI 57–82 (57); PPI 125–143 (127); PSI 10–14 (10).

Head longer than wide (CI 71–79), in full-face view nearly rectangular, about 1.5 times longer than wide. Posterior margin of head medially concave, posterolateral corners rounded, lateral margins straight to weakly convex. Mandibles with five teeth. Anterior margin of clypeus medially concave and laterally convex. Frons without median ocellus. Antennae with ten segments. Scapes short (HL 0.54–0.71, SL 0.21–0.27, SI 34–43) not surpassing cephalic midlength. Eyes present, consisting of one to three ommatidia (EL 0.01–0.03). Supraclypeal area well defined and triangular.

In profile, posterolateral corner of head with (larger major workers) or without (smaller major workers) a small, obtuse tooth resembling a horn. Promesonotum high and convex, metanotal groove deep. Propodeum about 1.5 times higher than long, dorsal face of propodeum flat or weakly concave, declining posteriorly, propodeum unarmed, posterodorsal corners of propodeum convex or angulate, declivity of propodeum flat to slightly concave in direction of propodeal lobe. Propodeal lobes triangular with blunt apices. Propodeal spiracle rounded and situated above mid-height of sclerite and beyond mid-length of sclerite, by about the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum almost twice the diameter of the spiracle, (PSL 0.04–0.07) and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides rounded; sides of propodeum convex.

Petiole approximately as high as long (PTH 0.14–0.20, PTL 0.15–0.24) and with a short peduncle, ventral face medially convex. Anterodorsal and posterodorsal faces of petiolar node sloping, combined outline of dorsal surface of peduncle and anterior face of node flat, posterior face of node vertical, straight to slightly convex, dorsum rounded. Subpetiolar process slightly shorter than the diameter of the propodeal spiracle. Postpetiolar node rounded and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PPW 0.16–0.23, PTW 0.12–0.17), petiolar node wider than long (PTW 0.12–0.17, PNL 0.08–0.11), anterior and posterior margins of petiole and postpetiole nearly straight, sides rounded in petiole and postpetiole.

Dorsal surface of mandibles, clypeus and frons smooth and shiny, with scattered piligerous punctae on head and mandibles. Dorsolateral faces of head longitudinally rugose, gena with well-developed longitudinal reticulations, weakly marked rugae on frontal lobes, reticulate-rugose sculpture near posterior margin of head. In profile, posterolateral portion of cephalic dorsum smooth and shiny. Mesosoma smooth and shiny, except for katepisternum and propodeal lobe (areolate-rugose), and metapleuron (areolate and with longitudinal rugae). Petiole and ventral face of postpetiole areolate-rugose. In dorsal view, mesosoma, petiole, postpetiole and gaster smooth and shiny.

Lateral margins, and posterolateral corners of head with short subdecumbent hairs, and longer suberect hairs. Scapes with appressed hairs. Outer margin of mandibles with short subdecumbent hairs. Mesosoma with short and long suberect hairs. Petiole, postpetiole and gaster with short decumbent hairs and sparse and slightly longer subdecumbent hairs. Tibia with short appressed hairs. Color yellowish ferruginous, antennae, legs and parts of gaster, slightly lighter.

Minor. (n=9): HL 0.33–0.37; HW 0.28– 0.34; SL 0.20–0.23; ML 0.08–0.10; EL 0.01–0.02; EM 0.09–0.10; HD 0.19–0.22; WL 0.33–0.38; PSL 0.02–0.04; PW 0.16–0.20; MFL 0.20–0.22; MFW 0.05; MTL 0.15–0.17; PTL 0.11–0.12; PNL 0.06–0.07; PTH 0.09–0.10; PTW 0.08–0.09; PPL 0.07–0.08; PPNL 0.06–0.08; PPH 0.07–0.08; PPW 0.09–0.12; GL 0.26–0.34; GW 0.20–0.25; CI 82–92; MI 24–27; SI 59–64; MLI 65–76; PPLI 58–67; PPI 113–138; PSI 7–14.

Head longer than wide (CI 82–92), in full-face view weakly subrectangular, about 1.2 times longer than wide, and slightly narrowed anteriorly. Posterior margin of head slightly concave in the middle, posterolateral corners rounded, lateral margins slightly convex, nearly straight. Mandibles with five teeth. Anterior margin of clypeus more or less straight, and laterally angulate. Antennae with ten segments. Scape fails to reach the posterior margin of head (HL 0.33–0.37, SL 0.20–0.23, SI 59–64). Eyes present, consisting of one ommatidium (EL 0.01–0.02). Supraclypeal area triangular, in some specimens poorly defined, and appears as a short longitudinal depression.

In profile view, promesonotum weakly convex, metanotal groove slightly impressed. Propodeum about 1.5 times higher than long, dorsal face convex and declining posteriorly, posterodorsal corners of propodeum each armed with a small angulate tooth, declivity of propodeum slightly concave. Propodeal lobes triangular. Propodeal spiracle rounded and situated slightly above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of the sclerite by about the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum same as the diameter of the spiracle (PSL 0.02–0.04), and distance to declivity less than the diameter of the spiracle. In dorsal view, promesonotum longer than wide, anterior margin rounded, sides convex; sides of propodeum weakly convex.

Petiole slightly longer than high (PTL 0.11–0.12, PTH 0.09–0.10) with a short peduncle, ventral face weakly convex in the middle. Combined outline of dorsal surface of peduncle and anterior face of node nearly straight, posterior margin slightly convex, dorsum rounded. Subpetiolar process small, almost the same as the diameter of the propodeal spiracle. Postpetiolar node convex and lower than petiolar node. In dorsal view, postpetiolar node slightly wider than petiolar node (PPW 0.09–0.12, PTW 0.08–0.0.9), petiolar node wider than long (PTW 0.09–0.12, PNL 0.06–0.07), anterior margin of petiole convex, posterior margin slightly concave, anterior and posterior margin of postpetiole nearly straight, sides moderately convex in petiole and postpetiole. Dorsal surface of mandibles, clypeus and frons smooth and shiny, with abundant piligerous punctae on mandibles and head. Head with fine and short longitudinal rugae on malar space and frontal lobes. Mesosoma smooth and shiny, except for katepisternum, below mid-height of metapleuron, and propodeal lobe, which are areolate-rugose. Sides of petiole, and ventral face of postpetiole areolate-rugose. In dorsal view, mesosoma, petiole, postpetiole and gaster smooth and shiny.

Lateral margins, scapes and posterior margin of head with subdecumbent hairs. Hairs in the posterior margin shorter than others. Outer margin of mandible with decumbent hairs. Mesosoma with suberect hairs. Petiole, postpetiole, tibia and gaster with short decumbent to subdecumbent hairs, and with sparse and slightly longer subdecumbent hairs. Tibia with abundant to sparse decumbent hairs. Color yellowish ferruginous.

Type Material
Holotype. (major worker), MADAGASCAR, Mahajanga, Forêt de Tsimembo, 11.0 km 346° NNW Soatana, -18.99528, 44.4435, 50 m, tropical dry forest, 21–25.xi.2001, (Fisher, Griswold et al.). Collection code BLF04508, (: CASENT0483010). Paratypes. (16 major workers and 22 minor workers), with same data as holotype, 15 major workers (: CASENT0482934, CASC: CASENT0483093, CASENT0483092, CASENT0483094, CASENT0482845, CASENT0483091, CASENT0483058, CASENT0482822, CASENT0482813, CASENT0482823, CASENT0483057, CASENT0482984, : CASENT0482830, : CASENT0483009, : CASENT0482821), and 22 minor workers (BMNH: CASENT0482990, CASC: CASENT0482991, CASENT0482983, CASENT0483028, CASENT0483023, CASENT0482978, CASENT0482977, CASENT0482994, CASENT0482985, CASENT0482999, CASENT0483033, CASENT0482992, CASENT0482993, CASENT0483011, CASENT0482996, CASENT0482998, CASENT0482987, CASENT0483021, CASENT0483022, MCZ: CASENT0482995, NHMB: CASENT0483037, BMNH: CASENT0482986). 1 major worker, Madagascar, Ma hajanga, Forêt de Tsimembo, 8.7 km 336° NNW Soatana, -19.02139, 44.44067, 20 m, tropical dry forest, 21–25.xi.2001, (Fisher, Griswold et al.) with collection code BLF04511, (CASC: CASENT0077891).