Carebara dota Azorsa & Fisher

Azorsa, Frank & Fisher, Brian L., 2018, Taxonomy of the ant genus Carebara Westwood (Formicidae, Myrmicinae) in the Malagasy Region, ZooKeys 767, pp. 1-149 : 1

Carebara dota Azorsa & Fisher sp. n.

Holotype.

(major worker), MADAGASCAR, Fianarantsoa , 43 km S Ambalavao, Réserve Andringitra, -22.23333, 47, 825 m, rainforest, 5.x.1993, (B.L. Fisher). Collection code BLF00747, (CASC: CASENT0192623). Paratypes: (5 major workers and 19 minor workers), with same data as holotype, 5 major workers (BMNH: CASENT0248460, CASC: CASENT0281313, CASENT0127684, CASENT0127650, CASENT0127649), and 19 minor workers (BMNH: CASENT0004053, CASC: CASENT0004050, CASENT0002885, CASENT0004051, CASENT0002887, CASENT0002886, CASENT0002884, CASENT0002882, CASENT0002883, CASENT0004057, CASENT0004052, CASENT0004056, CASENT0004049, CASENT0004055, CASENT0127703, CASENT0192570, MCZ: CASENT0227028, MHNG: CASENT0227023, NHMB: CASENT0127685).

Diagnosis.

Antennae ten-segmented. Major: Head longer than wide, lateral margins straight, head with longitudinal and parallel rugae, reticulate rugose close to posterolateral corners of head; promesonotum strongly convex, dorsum of propodeum slightly convex, nearly flat, posterodorsal corners with small angulate tooth; combined outline of dorsal surface of peduncle and anterior face of node slightly concave, posterior margin vertical and nearly straight; gaster with subdecumbent hairs. Minor: Head longer than wide, lateral margins slightly convex; propodeum with small, triangular, angulate teeth; combined outline of dorsal surface of peduncle and anterior face of node nearly straight, posterior margin vertical and concave.

Description of major workers.

Measurements (n=7): HL 0.61-0.71 (0.62); HW 0.47-0.56 (0.50); SL 0.22-0.28 (0.25); ML 0.12-0.15 (0.12); EL 0.02-0.03 (0.02); EM 0.15-0.19 (0.18); HD 0.35-0.41 (0.36); WL 0.53-0.62 (0.53); PSL 0.05-0.07 (0.05); PW 0.33-0.40 (0.35); MFL 0.30-0.36 (0.32); MFW 0.08-0.09 (0.08), MTL 0.20-0.27 (0.23); PTL 0.19-0.23 (0.19); PNL 0.09-0.10 (0.09); PTH 0.15-0.18 (0.15); PTW 0.13-0.16 (0.14); PPL 0.13-0.16 (0.13); PPNL 0.11-0.14 (0.12); PPH 0.13-0.16 (0.14); PPW 0.17-0.22 (0.19); GL 0.47-0.60 (0.50); GW 0.39-0.55 (0.39); CI 77-83 (81); MI 19-21 (19); SI 35-41 (40), MLI 58-64 (64); PPLI 62-74 (68); PPI 129-143 (136); PSI 9-13 (10).

Head longer than wide (CI 77-83), in full-face view nearly subrectangular, about 1.3 times longer than wide. Posterior margin of head medially concave, posterolateral corners rounded, lateral margins straight. Mandibles with five teeth. Anterior margin of clypeus slightly concave, and laterally angulate. Antennae with ten segments. Scapes short (HL 0.61-0.71, SL 0.22-0.28, SI 35-41). Eyes present, consisting of two ommatidia (EL 0.02-0.03). Supraclypeal area triangular and well defined.

In profile, posterolateral corner of head with a small, triangular tooth resembling a horn. Promesonotum high and strongly convex, metanotal groove deeply impressed. Propodeum lower than promesonotum. Propodeum about 1.8 times higher than long, dorsal face of propodeum slightly convex, nearly flat, declining posteriorly, posterodorsal corners each armed with a very small angulate tooth, declivity of propodeum vertical and concave with thin lateral laminae. Propodeal lobes triangular. Propodeal spiracle nearly oval and situated above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum about two times the diameter of the spiracle (PSL 0.05-0.07), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about as long as wide (1.1 times longer than wide), anterior margin and sides of promesonotum rounded; sides of propodeum weakly convex.

Petiole approximately as high as long (PTH 0.15-0.18, PTL 0.19-0.23) and with a relatively short peduncle, ventral face slightly convex in the middle. Combined outline of dorsal surface of peduncle and anterior face of node concave, posterior face of node vertical and nearly straight, anterodorsal corner convex, posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as a small denticle, almost as large as the diameter of the propodeal spiracle. Postpetiolar node strongly convex and lower than petiolar node. In dorsal view, petiolar node not as broad as postpetiolar node (PTW 0.13-0.16, PPW 0.17-0.22) and petiolar node wider than long (PNL 0.09-0.10, PTW 0.13-0.16), anterior and posterior margins of petiole straight, anterior margin of postpetiole concave, posterior margin nearly straight, sides of petiole rounded and strongly convex in postpetiole.

Dorsal surface of mandibles, clypeus and supraclypeal area smooth and shiny, with scattered piligerous punctae on mandibles and head. Head with well defined longitudinal rugae, and reticulate rugose near the posterior margin, gena with longitudinal rugae extending to the posterolateral corners. In profile, posterolateral portion of cephalic dorsum smooth and shiny but with finely longitudinal reticulations. Mesosoma smooth and shiny, except for katepisternum (areolate), and metapleuron (finely areolate and with longitudinal rugae). Petiole and ventral face of postpetiole areolate. In dorsal view mesosoma, petiole, postpetiole and gaster, smooth and shiny except for declivity, anterior face of petiole and postpetiole which are finely areolate.

Lateral margins of head with short subdecumbent hairs, posterolateral corners with scattered suberect hairs. Scapes with appressed hairs. Outer margin of mandibles with short appressed hairs. Mesosoma with short and long suberect hairs, petiole and postpetiole with decumbent hairs and longer subdecumbent hairs. Tibia with decumbent hairs. Gaster with abundant subdecumbent hairs. Color yellowish.

Description of minor workers.

Measurements (n=8): HL 0.38-0.41; HW 0.33-0.36; SL 0.23-0.25; ML 0.09-0.11; EL 0.01-0.02; EM 0.10-0.11; HD 0.20-0.25; WL 0.39-0.42; PSL 0.03-0.04; PW 0.18-0.24; MFL 0.23-0.29; MFW 0.06-0.07; MTL 0.15-0.21; PTL 0.12-0.16; PNL 0.06-0.07; PTH 0.11-0.13; PTW 0.09-0.10; PPL 0.08-0.10; PPNL 0.08-0.09; PPH 0.08-0.10; PPW 0.12-0.14; GL 0.32-0.42; GW 0.26-0.30; CI 80-92; MI 22-27; SI 58-63; MLI 69-83; PPLI 53-83; PPI 130-144; PSI 9-12.

Head longer than wide (CI 80-92), in full-face view nearly subquadrate, about 1.1 times longer than wide, weakly narrowed anteriorly. Posterior margin of head slightly concave in the middle, posterolateral corners rounded, lateral margins slightly convex. Mandibles with five teeth. Anterior margin of clypeus medially convex, and laterally angulate. Antennae with ten segments. Scape fails to reach the posterior margin of head (HL 0.38-0.41, SL 0.23-0.25, SI 58-63). Eyes present, consisting of one ommatidium (EL 0.01-0.02). Supraclypeal area triangular and well defined.

In profile view, promesonotum weakly convex, metanotal groove deeply impressed. Propodeum about 1.65 times higher than long, dorsal face of propodeum nearly flat and declining posteriorly, posterodorsal corners of propodeum each armed with a small triangular tooth, anterodorsal corner of propodeum convex, declivity vertical and concave with thin lateral laminae. Propodeal lobes triangular. Propodeal spiracle rounded and situated above mid-height of sclerite by about the diameter of the spiracle, and beyond mid-length of sclerite by about two times the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum almost twice the diameter of the spiracle (PSL 0.03-0.04), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about as long as wide (1.1 times longer than wide), anterior margin weakly convex, sides convex and narrowed posteriorly; sides of propodeum straight to weakly convex.

Petiole about as high as long (PTL 0.12-0.16, PTH 0.11-0.13) and with a short peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node nearly straight, posterior face of node vertical and slightly concave, anterodorsal corner convex, posterodorsal corner rounded, dorsum slightly convex. Subpetiolar process produced as a small denticle, almost as large as the diameter of the propodeal spiracle. Postpetiolar node convex and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PPW 0.12-0.14, PTW 0.09-0.10), petiolar node wider than long (PNL 0.06-0.07, PTW 0.09-0.10), anterior and posterior margin of petiole nearly straight, anterior margin of postpetiole slightly concave, posterior margin convex, sides of petiole convex and rounded in postpetiole.

Dorsal surface of mandibles, median portion of clypeus and supraclypeal area smooth and shiny, with scattered piligerous punctae on head and mandibles, except for smooth and shiny frons; malar area and frontal lobes with longitudinal rugae. Mesosoma smooth and shiny, except for katepisternum (areolate), and metapleuron (weakly areolate and with longitudinal and parallel rugae). Petiole and ventral face of postpetiole areolate. In dorsal view, mesosoma, petiole, postpetiole and gaster smooth and shiny.

Lateral margins of head with subdecumbent hairs, posterior margin of head with suberect hairs. Scapes with abundant decumbent hairs. Outer margin of mandible with decumbent hairs. Mesosoma with short and long suberect hairs. Petiole and postpetiole with short decumbent hairs and longer subdecumbent hairs. Tibia with abundant decumbent hairs. Gaster with abundant subdecumbent hairs, and sparse suberect hairs. Color yellowish ferruginous.

Distribution and biology.

Carebara dota is known only from southwestern and north-central Madagascar (Figure 68). This species was found in habitats such as gallery forest, grassland, littoral rainforest, montane rainforest, montane rainforest edge, and rainforest. C. dota was collected at elevations ranging from 10 m to 1670 m using maxi-Winkler and pitfall traps. Individuals and colonies were found in leaf mold and rotten wood.

Comments.

Carebara dota is endemic to Madagascar, and major workers are easily distinguished from other species by the longitudinal and parallel rugae on the dorsal surface of the head. Six species were recorded at the same places were this species was collected: C. bara , C. grandidieri , C. hainteny , C. jajoby , C. nosindambo , and C. sampi , which can be separated from C. dota by the characters mentioned above.

C. dota does not have intermediates in the major worker subcaste.

Additional material examined.

MADAGASCAR: Fianarantsoa : 45 km S. Ambalavao, -22.21667, 47.01667, 785 m, rainforest, 25.ix.1993, (B.L. Fisher); Fianarantsoa , 28 km SSW Ambositra, Ankazomivady, -20.775, 47.16833, 1670 m, grassland, 11.i.1998, (B.L. Fisher); Fianarantsoa , Réserve Spéciale Ivohibe, 7.5 km ENE Ivohibe, -22.47, 46.96, 900 m, rainforest, 7-12.x.1997, (B.L.Fisher (Sylvain)); Fianarantsoa , 28 km SSW Ambositra, Ankazomivady, -20.775, 47.16833, 1670 m, montane rainforest edge, 14.i.1998, (B.L. Fisher); Toliara : Manombo, -22.8123, 43.73932, 165 m, gallery forest, TS3, 22-24.v.2004, (Frontier Wilderness Project); Toliara , Parc National d’Andohahela, Col du Sedro, 3.8 km 113° ESE Mahamavo, 37.6 km 341° NNW Tolagnaro, -24.76389, 46.75167, 900 m, montane rainforest, 21-25.i.2002, (Fisher, Griswold et al.); Toliara , Réserve Spéciale Kalambatritra, Ampanihy, -23.4635, 46.4631, 1270 m, montane rainforest, 9-10.ii.2009, (B.L. Fisher et al.); Toliara , Forêt de Petriky, 12.5 km W 272° Tolagnaro, -25.06167, 46.87, 10 m, littoral rainforest, 22.xi.1998, (B.L. Fisher).