Carebara lova 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 lova Azorsa & Fisher sp. n.

Holotype.

(major worker), MADAGASCAR, Mahajanga , Parc National d’Ankarafantsika, Ampijoroa Station Forestière, 5.4 km 331° NW Andranofasika, -16.29889, 46.813, 70 m, tropical dry forest, 26.iii.01.iv.2001, (Fisher, Griswold et al.). Collection code BLF03571, (CASC: CASENT0468707). Paratypes: (12 major workers and 17 minor workers), with same data as holotype, 12 major workers (BMNH: CASENT0468552, CASC: CASENT0468675, CASENT0468639, CASENT0468605, CASENT0468494, CASENT0468503, CASENT0468578, CASENT0431674, CASENT0468476, MCZ: CASENT0468685, MHNG: CASENT0468659, NHMB: CASENT0468474), and 17 minor workers (BMNH: CASENT0468630, CASC: CASENT0468621, CASENT0468626, CASENT0468562, CASENT0468579, CASENT0468548, CASENT0468704, CASENT0468701, CASENT0468693, CASENT0468593, CASENT0468599, CASENT0468690, CASENT0468551, CASENT0468694, MCZ: CASENT0468668, MHNG: CASENT0468635, NHMB: CASENT0468673).

Diagnosis.

Antennae ten-segmented. Major: Head longer than wide, posterior margin of head deeply concave; dorsum of propodeum flat and declining posteriorly, posterodorsal corner of propodeum with small triangular teeth; combined outline of dorsal surface of peduncle and anterior face of node medially concave, posterior face vertical and slightly convex; gaster with sparse, short appressed hairs, and dispersed longer suberect hairs. Minor: Head longer than wide, posterior margin of head nearly straight; propodeum slightly convex and declining posteriorly, nearly flat, posterodorsal corner of propodeum with a very small triangular tooth; gaster with short decumbent to appressed hairs, and dispersed longer suberect hairs.

Description of major workers.

Measurements (n=36): HL 0.60-1.05 (0.72); HW 0.49-0.85 (0.56); SL 0.25-0.37 (0.28); ML 0.14-0.26 (0.19); EL 0.01-0.08 (0.03); EM 0.17-0.32 (0.20); HD 0.33-0.63 (0.40); WL 0.51-0.96 (0.60); PSL 0.05-0.12 (0.07); PW 0.30-0.57 (0.36); MFL 0.30-0.53 (0.33); MFW 0.07-0.12 (0.08); MTL 0.22-0.41 (0.27); PTL 0.19-0.39 (0.23); PNL 0.09-0.17 (0.10); PTH 0.10-0.26 (0.17); PTW 0.13-0.25 (0.15); PPL 0.12-0.22 (0.14); PPNL 0.11-0.21 (0.12); PPH 0.12-0.27 (0.15); PPW 0.17-0.36 (0.20); GL 0.42-1.40 (0.60); GW 0.41-0.88 (0.48); CI 75-90 (78); MI 22-27 (26); SI 32-43 (39), MLI 57-65 (59); PPLI 54-90 (61); PPI 117-150 (133); PSI 10-15 (13).

Head longer than wide (CI 75-90), in full-face view nearly subrectangular, about 1.3 times longer than wide, slightly narrowed posteriorly. Posterior margin of head deeply concave, posterolateral corners well developed and rounded, lateral margins slightly convex. Mandibles with six teeth. Anterior margin of clypeus nearly straight, weakly concave, and laterally convex. Antennae with ten segments. Scapes short (HL 0.60-1.05, SL 0.25-0.37, SI 32-43) not surpassing cephalic midlength. Ocelli present or absent. Eyes present, consisting of one to three ommatidia (EL 0.01-0.08). Supraclypeal area short and triangular.

In profile view, posterolateral corner of head with a small angulate triangular tooth resembling a horn. Promesonotum high and nearly rounded, metanotal groove deeply impressed. Propodeum lower than promesonotum, and about 1.5 times higher than long, dorsal face of propodeum nearly flat, and declining posteriorly, propodeum armed, posterodorsal corners each armed with a small laminate triangular tooth, declivity concave with thin lateral laminae. Propodeal lobes short and convex. Propodeal spiracle nearly oval and situated slightly above mid-height of sclerite, and barely 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 0.05-0.12), and distance to declivity about 1.8 times the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides rounded, slightly narrowed anteriorly and posteriorly; sides of propodeum straight.

Petiole longer than high (PTL 0.19-0.39, PTH 0.10-0.26) and with relatively short peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node medially concave, posterior face of node vertical and weakly convex, anterodorsal corner convex, posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as denticle, slightly larger than the diameter of the propodeal spiracle. Postpetiolar node convex and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.13-0.25, PPW 0.17-0.36) and petiolar node wider than long (PNL 0.09-0.17, PTW 0.13-0.25), anterior margin of petiole convex, posterior margin nearly straight, anterior margin of postpetiole concave, and convex posterior margin, sides rounded in petiole and postpetiole.

Dorsal surface of mandibles, clypeus, supraclypeal area and frons smooth and shiny, with scattered piligerous punctae on head and mandibles. Dorsolateral faces of head with longitudinal rugae, gena and frontal lobes with longitudinal rugae extending to posterior border of posterolateral corners. In profile, posterolateral portion of cephalic dorsum smooth and shiny. Mesosoma smooth and shiny, except for katepisternum and metapleuron, which are longitudinally areolate-rugose. Petiole, ventral face, and lateral margins of postpetiole areolate. In dorsal view, promesonotum, petiole, postpetiole and gaster smooth and shiny, except for propodeum which is finely areolate.

Lateral margins of head with short appressed hairs and long suberect hairs. Posterior margin of head with short and long suberect hairs. Scapes with appressed hairs. Outer margin of mandibles with sparse and short appressed hairs. Mesosoma with short and long suberect hairs. Petiole and postpetiole with short decumbent to appressed hairs and long subdecumbent hairs. Tibia with appressed hairs. Gaster with short decumbent to appressed hairs and dispersed, long suberect hairs. Color yellowish ferruginous.

Description of minor workers.

Measurements (n=26): HL 0.32-0.38; HW 0.28-0.35; SL 0.20-0.24; ML 0.08-0.10; EL 0.01-0.02; EM 0.09-0.12; HD 0.20-0.23; WL 0.32-0.40; PSL 0.03-0.05; PW 0.11-0.20; MFL 0.20-0.25; MFW 0.05-0.06; MTL 0.15-0.19; PTL 0.11-0.14; PNL 0.05-0.07; PTH 0.09-0.11; PTW 0.08-0.09; PPL 0.07-0.10; PPNL 0.06-0.09; PPH 0.06-0.09; PPW 0.10-0.13; GL 0.26-0.39; GW 0.19-0.29; CI 83-95; MI 21-27; SI 60-65; MLI 65-78; PPLI 57-73; PPI 122-150; PSI 9-16.

Head longer than wide (CI 83-95), in full-face view nearly subquadrate, about 1.1 times longer than wide, narrowed anteriorly and posteriorly. Posterior margin of head nearly straight to weakly concave medially, posterolateral corners rounded, lateral margins convex. Mandibles with five teeth. Anterior margin of clypeus nearly straight, and laterally convex. Antennae with ten segments. Scape fails to reach the posterior margin of head (HL 0.32-0.38, SL 0.20-0.24, SI 60-65). Eyes present, consisting of one ommatidium (EL 0.01-0.02). Supraclypeal area triangular but not well defined.

In profile, promesonotum slightly convex, nearly flat, metanotal groove present. Propodeum about 1.4 times higher than long, dorsal face of propodeum nearly flat to weakly convex, and declining posteriorly, propodeum armed, posterodorsal corners each armed with a small triangular tooth, declivity concave with thin lateral laminae. Propodeal lobes short and convex. Propodeal spiracle rounded 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 almost the same as the diameter of the spiracle (PSL 0.03-0.05), and distance to declivity less than half the diameter of the spiracle. In dorsal view, anterior margin of promesonotum convex, sides rounded and narrowed posteriorly, slightly longer than wide; sides of propodeum straight.

Petiole longer than high (PTL 0.11-0.14, PTH 0.09-0.11) and with relatively short peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node medially concave, posterior face of node weakly convex, anterodorsal corner convex and posterodorsal corner rounded, dorsum nearly rounded. Subpetiolar process produced as a small denticle, weakly shorter than the diameter of the propodeal spiracle. Postpetiolar node nearly rounded and lower than petiolar node. In dorsal view, postpetiolar node slightly wider than petiolar node (PTW 0.08-0.09, PPW 0.10-0.13), and petiolar node wider than long (PNL 0.05-0.07, PTW 0.08-0.09), anterior margin of petiole convex, posterior margin nearly straight, anterior and posterior margin of postpetiole nearly straight, sides of petiole and postpetiole rounded.

Dorsal surface of mandibles, clypeus, supraclypeal area and frons smooth and shiny, with scattered piligerous punctae on head and mandibles. Gena and frontal lobes with longitudinal rugae. Mesosoma smooth and shiny, except for katepisternum, metapleuron and propodeum which are areolate. Petiole and ventral face of postpetiole areolate. In dorsal view, promesonotum, postpetiole and gaster smooth and shiny; propodeum and petiole areolate.

Posterior and lateral margins of head with short decumbent hairs. Scapes with appressed hairs. Outer margin of mandibles with short appressed hairs. Mesosoma with short suberect hairs and long erect hairs. Petiole and postpetiole with short decumbent hairs and long subdecumbent hairs. Tibia with appressed hairs. Gaster with short decumbent hairs and long suberect hairs. Color yellowish ferruginous.

Distribution and biology.

Carebara lova is known only from Madagascar, distributed in the northwestern part of the island (Figure 68). This species occurs in the following ecosystems: gallery forest, gallery forest on sandy soil, rainforest and tropical dry forest. It was collected at elevations ranging from 30 m to 500 m. Individuals and colonies were found in sifted litter, rotten logs, leaf mold, and rotten wood. All specimens were collected using maxi-Winkler and pitfall traps.

Comments.

Carebara lova can be confused with C. sampi but can be separated by the distance from posterior border of propodeal spiracle to declivity, which is less than two times the diameter of the spiracle in C. sampi and is same as or less than the diameter of the spiracle in C. lova . C. lova is distributed in the northwestern area of Madagascar while C. sampi is distributed in the south and southwestern of Madagascar. Other two species were recorded at the same localities: C. bara , and C. grandidieri .

C. lova have three intermediates in the major worker subcaste (Figure 48). The posterolateral corner of the head of intermediates 2 and 3 is nearly rounded, and slightly narrowed posteriorly in intermediate 1; the posterior margin of the head is deeply concave in all intermediates. The lateral margins of the head are nearly straight in bigger major workers, and slightly convex in smaller and medium major workers. The eyes are small and reduced to one ommatidium in the smaller and medium intermediates,but may consist of up to four ommatidia in the bigger ones. Ocelli are absent in the smaller and medium major workers, but present and well developed in the big major workers (one ocellus). Reduced flight sclerites are present in the largest intermediate. The dorsum of the mesosoma is convex anteriorly and gradually slopes to the declivity in intermediate 3. The dorsum of the promesonotum is high and strongly convex in intermediates 1 and 2. The shape of the petiole and postpetiole vary little in all intermediates, although the anterior margin of the petiole is nearly straight in intermediate 3 and the petiolar node is thinner than that of intermediates 1 and 2. The propodeum is armed with a pair of triangular teeth in all intermediates. Frons smooth and shiny, dorsolateral faces with finely longitudinal and parallel rugae in full-face view in all intermediates. The pilosity on the head and body follows the same pattern in all intermediates, with intermediate 3 with more abundant, short decumbent hairs on the gaster.

Additional material examined.

MADAGASCAR: Mahajanga : Parc National de Namoroka, 17.8 km 329° WNW Vilanandro, -16.37667, 45.32667, 100 m, tropical dry forest, 8-12.xi.2002, (Fisher, Griswold et al.); Mahajanga , Réserve Spéciale de Bemarivo, 23.8 km 223° SW Besalampy, -16.925, 44.36833, 30 m, tropical dry forest, 19-23.xi.2002, (Fisher, Griswold et al.); Mahajanga , Parc National de Namoroka, 16.9 km 317° NW Vilanandro, -16.40667, 45.31, 100 m, tropical dry forest, 12-16.xi.2002, (Fisher, Griswold et al.); Mahajanga , Parc National d’Ankarafantsika, Forêt de Tsimaloto, 18.3 km 46° NE de Tsaramandroso, -16.22806, 47.14361, 135 m, tropical dry forest, 2-8.iv.2001, (Fisher, Griswold et al.); Mahajanga , Réserve d’Ankoririka, 10.6 km 13° NE de Tsaramandroso, -16.26722, 47.04861, 210 m, tropical dry forest, 9-14.iv.2001, (Fisher, Griswold et al.); Mahajanga , Mahavavy River, 6.2 km 145° SE Mitsinjo, -16.05167, 45.90833, 20 m, gallery forest, 1-5.xii.2002, (Fisher, Griswold et al.).