Carebara grandidieri

Carebara grandidieri is a widespread, common species in the Malagasy region. Individuals and colonies have been collected from rotten logs, rotting tree stumps, soil, termite mounds, leaf litter, under moss, litter on rocks, under rotten logs, under stones, and in leaf litter. (Azorsa & Fisher, 2018)

Identification
Azorsa and Fisher (2018) - Antennae nine-segmented. Major: Head longer than wide, nearly rectangular, margins straight and parallel; petiole with relatively long peduncle, ventral face flat, petiolar node rounded. Minor: Head longer than wide, nearly subrectangular; petiole with relatively long peduncle, petiolar node rounded.

Carebara grandidieri is widely distributed throughout Madagascar, Comoros and Mayotte, and co-occurs with almost all Carebara species recorded in the Malagasy region. The morphology of this species is highly variable a) pilosity that varies from suberect to decumbent hairs, and is more noticeable on the gaster; b) posterior corner of propodeum, which varies from a pair of small triangular and angulate upwardly directed teeth, to nearly convex (in specimens from the same colony it is possible to see the gradual change from nearly convex to slightly dentate); c) petiole, where the node is thicker in profile and dorsal view, in some populations; and d) the diameter of the propodeal spiracle, which is smaller in populations from the north of Madagascar. In the Malagasy region there are only two species of Carebara with nine antennal segments: C. grandidieri and Carebara creolei. Carebara creolei is present only in Comoros and the Seychelles. All other Carebara species present in Madagascar have 10 or 11 antennal segments.

The queen of C. grandidieri can be separated from others by the following combination of characters: head longer than wide, in full-face view nearly rectangular, or nearly subquadrate, posterior margin of head slightly concave in the middle, posterolateral corners rounded; lateral margins straight to slightly convex; mandible with six or seven teeth; anterior margin of clypeus slightly concave; antennae with nine segments; ocelli present, eyes present.

Distribution
Azorsa and Fisher (2018) - Madagascar, Comoros and Mayotte. This species was collected in the following environments: along the roadside, coastal scrub, dry forest, gallery forest, grassland, littoral forest, montane rainforest, open secondary vegetation, rainforest, spiny forest/thicket, tropical dry forest, Uapaca woodland, and urban/garden. C. grandidieri was sampled at elevations ranging from 10 m to 1550 m.

Distribution based on Regional Taxon Lists
Afrotropical Region: Comoros. Malagasy Region: Madagascar, Mayotte.

Nomenclature

 *  grandidieri. Oligomyrmex grandidieri Forel, 1891b: 201 (q.) MADAGASCAR.
 * Forel, 1895c: 250 (m.).
 * Combination in Carebara: Fernández, 2004a: 235.
 * Senior synonym of voeltzkowi: Azorsa & Fisher, 2018: 58.
 * voeltzkowi. Oligomyrmex voeltzkowi Forel, 1907g: 77 (q.) MADAGASCAR.
 * Combination in Carebara: Fernández, 2004a: 235.
 * Junior synonym of grandidieri: Azorsa & Fisher, 2018: 58.

Worker
Azorsa and Fisher (2018) - Major. (n=22): HL 0.56–0.84; HW 0.44–0.61; SL 0.25–0.32; ML 0.12–0.21; EL 0.01–0.03; EM 0.14–0.19; HD 0.30– 0.45; WL 0.51–0.74; PSL 0.05–0.09; PW 0.26–0.38; MFL 0.29–0.42; MFW 0.06– 0.10; MTL 0.26–0.37; PTL 0.18–0.28; PNL 0.09–0.14; PTH 0.12–0.20; PTW 0.12–0.19; PPL 0.11–0.16; PPNL 0.09–0.14; PPH 0.10–0.17; PPW 0.13–0.21; GL 0.44–0.85; GW 0.35–0.65; CI 71–79; MI 20–27; SI 38–46; MLI 63–74; PPLI 50– 67; PPI 100–123; PSI 10–15.

Head longer than wide (CI 71–79), 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 six teeth. Anterior margin of clypeus concave and laterally convex. Frons without median ocellus. Antennae with nine segments. Scapes short (HL 0.56–0.84, SL 0.25–0.32, SI 38–46). Eyes present, consisting of one to three ommatidia (EL 0.01–0.03). Supraclypeal area acutely triangular, extending forward beyond the antennal insertions.

In profile view, promesonotum convex, mesonotum shallowly present and lower than dorsum of promesonotum, metanotal groove present. Propodeum lower than promesonotum, about 1.2 times higher than long, dorsal face of propodeum nearly flat and declining posteriorly, posterodorsal corner angulate to dentate, declivity of propodeum slightly concave with thin lateral laminae in direction of propodeal lobe. Propodeal lobes short and convex. Propodeal spiracle rounded and situated above mid-height of sclerite, and beyond mid-length of sclerite by about half the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum about 2.5 times the diameter of the spiracle (PSL 0.05–0.09), and distance to declivity almost twice the diameter of the spiracle. In dorsal view, promesonotum about 1.2 times longer than wide, anterior margin of promesonotum rounded, sides convex and narrowed posteriorly; sides of propodeum weakly convex or straight.

Petiole with relatively long peduncle, ventral face flat. Combined outline of dorsal surface of peduncle and anterior face of node deeply concave in the middle, posterior face of node slightly convex, anterodorsal and posterodorsal corner convex, dorsum rounded. Subpetiolar process produced as a small denticle, smaller than the diameter of the propodeal spiracle. Postpetiolar node rounded and lower than petiolar node. In dorsal view, petiolar node as broad as postpetiolar node (PTW 0.12–0.19, PPW 0.13–0.21) and petiolar node wider than long (PNL 0.09–0.14, PTW 0.12–0.19), anterior and posterior margins of petiole nearly straight, anterior margin of postpetiole concave and convex posterior margin, sides rounded in petiole and convex in postpetiole, narrowed posteriorly.

Dorsal surface of mandibles, upper median portion of clypeus and supraclypeal area smooth and shiny, with scattered piligerous punctae on head and mandibles. Head with longitudinal rugae along the gena, and frontal lobes. Lower median portion of clypeus with transverse rugae. In profile, posterolateral portion of cephalic dorsum smooth and shiny. Mesosoma smooth and shiny, except for propleuron and mesopleuron (areolate), and metapleuron (longitudinally rugulose). Ventral face of petiole and postpetiole longitudinally areolate. In dorsal view mesosoma, petiole, postpetiole and gaster smooth and shiny, except for declivity of propodeum, anterior and posterior face of petiole finely areolate.

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

Minor. (n=18): HL 0.39–0.49; HW 0.31–0.40; SL 0.23–0.30; ML 0.08–0.13; EL 0.01–0.02; EM 0.11–0.13; HD .022– 0.28; WL 0.40–0.52; PSL 0.03–0.05; PW 0.18–0.24; MFL 0.24–0.31; MFW 0.06– 0.08; MTL 0.19–0.27; PTL 0.16–0.19; PNL 0.09–0.11; PTH 0.10–0.13; PTW 0.09–0.11; PPL 0.08–0.11; PPNL 0.07–0.10; PPH 0.07–0.10; PPW 0.10–0.12; GL 0.31–0.55; GW 0.22–0.32; CI 79–86; MI 19–28; SI 57–65; MLI 73–82; PPLI 47– 63; PPI 100–120; PSI 9–13.

Head longer than wide (CI 79–86), in full-face view nearly subrectangular, about 1.2 times longer than wide. Posterior margin of head weakly concave, nearly straight, posterolateral corners rounded, lateral margins slightly convex, nearly straight. Mandibles with five teeth. Anterior margin of clypeus concave and laterally angulate. Antennae with nine segments. Scape fails to reach the posterior margin of head (HL 0.39–0.49, SL 0.23–0.30, SI 57–65). Eyes present, consisting of one ommatidium (EL 0.01–0.02). Supraclypeal area triangular but poorly defined.

In profile view, promesonotum weakly convex, nearly flat, metanotal groove present. Propodeum about 1.3 times higher than long, dorsal face of propodeum convex, posterodorsal corners angulate, or with a small triangular tooth, anterodorsal corner convex, declivity concave with thin lateral laminae in direction of propodeal lobe. Propodeal lobes short and triangular. Propodeal spiracle rounded and situated above mid-height of sclerite by about two times the diameter of the spiracle, and beyond mid-length of sclerite by about 1.5 times the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum almost three times the diameter of the spiracle (PSL 0.03–0.05), and distance to declivity less than twice the diameter of the spiracle. In dorsal view, promesonotum about 1.25 times longer than wide, anterior margin rounded, sides convex; sides of propodeum straight.

Petiole with a relatively long peduncle, petiole longer than high (PTL 0.16–0.19, PTH 0.10–0.13), ventral face flat. Combined outline of dorsal surface of peduncle and anterior face of node deeply concave in the middle, posterior face of node slightly convex, anterodorsal and posterodorsal corner convex, dorsum rounded. Subpetiolar process produced as a small denticle, smaller than the diameter of the propodeal spiracle. Postpetiolar node strongly convex and lower than petiolar node. In dorsal view, petiolar node almost as broad as postpetiolar node (PTW 0.09–0.11, PPW 0.10–0.12), and petiolar node as broad as long (PNL 0.09–0.11, PTW 0.09–0.11), anterior and posterior margin of petiole convex, anterior margin of postpetiole concave and convex posteriorly, sides of petiole and postpetiole strongly convex.

Dorsal surface of mandibles, clypeus, supraclypeal area, and head smooth and shiny, with scattered piligerous punctae on head and mandibles. Head with transverse rugae near the posterior margin of head, gena and frontal lobes with longitudinal rugae. Mesosoma smooth and shiny, except for propleuron and mesopleuron (areolate), and metapleuron (finely areolate-rugose). Lateral margins of petiole finely areolate-rugose, except for petiolar node and ventral face of postpetiole which are areolate. In dorsal view mesosoma, petiole, postpetiole and gaster smooth and shiny, except for declivity of propodeum, anterior and posterior face of petiole which are finely areolate.

Lateral margins of head and scape with subdecumbent to decumbent hairs. Posterior margin of head with short suberect hairs. Outer margin of mandibles with decum bent hairs. Mesosoma with short and long suberect hairs. Petiole and postpetiole with short decumbent hairs and long subdecumbent hairs. Tibia with decumbent hairs. Gaster with longer suberect to decumbent hairs. Color yellowish ferruginous.

Type Material
Azorsa and Fisher (2018) - Holotype queen (1 queen, CASENT0101999), [examined]: Madagascar, Antananarivo (Camboué).

References based on Global Ant Biodiversity Informatics

 * Azorsa F., and B. L. Fisher. 2018. Taxonomy of the ant genus Carebara Westwood (Formicidae, Myrmicinae) in the Malagasy Region. ZooKeys 767: 1-149.
 * Ettershank G. 1966. A generic revision of the world Myrmicinae related to Solenopsis and Pheidologeton (Hymenoptera: Formicidae). Aust. J. Zool. 14: 73-171.
 * Fisher B. L. 1997. Biogeography and ecology of the ant fauna of Madagascar (Hymenoptera: Formicidae). Journal of Natural History 31: 269-302.
 * Fisher B. L. 2003. Formicidae, ants. Pp. 811-819 in: Goodman, S. M.; Benstead, J. P. (eds.) 2003. The natural history of Madagascar. Chicago: University of Chicago Press, xxi + 1709 pp.
 * Forel A. 1895. Nouvelles fourmis de l'Imerina oriental (Moramanga etc.). Annales de la Société Entomologique de Belgique 39: 243-251.
 * Forel A. 1907. Ameisen von Madagaskar, den Comoren und Ostafrika. Wissenschaftliche Ergebnisse. Reise in Ostafrika 2: 75-92.
 * Goodman S., Y. Anbdou, Y. Andriamiarantsoa, B. L. Fisher, O. Griffiths, B. Keitt, J. J. Rafanomezantsoa, E. Rajoelison, J. C. Rakotonirina, L. Ranaivoarisoa et al. 2017. Results of a biological inventory of the Nosy Ankao island group, Parc National de Loky-Manambato, northeastern Madagascar. Malagasy Nature, Association Vahatra, 2017, 11, 
 * Wheeler W. M. 1922. Ants of the American Museum Congo expedition. A contribution to the myrmecology of Africa. IX. A synonymic list of the ants of the Malagasy region. Bulletin of the American Museum of Natural History 45: 1005-1055