Pachycondyla sikorae Forel

Rakotonirina, J. C. & Fisher, B. L., 2013, Revision of the Pachycondyla sikorae species-group (Hymenoptera: Formicidae) in Madagascar, Zootaxa 3683 (4), pp. 447-485 : 474-476

Pachycondyla sikorae Forel

(Figures 11, 58, 59, 60, 78)

Ponera (Euponera) sikorae Forel 1891 : 127. Lectotype worker, Madagascar Central (Sikora), present designation, specimen code: CASENT0101862 (MHNG) [examined]. [Accepted by Dalla Torre 1893: 42. Raised to genus and combination in Euponera (Euponera) by Emery 1901: 46, 1911: 83, Wheeler 1922: 1008. Combination in Pachycondyla by Brown in Bolton 1995: 309].

WORKER. Diagnosis: Anterior margin of clypeus broadly transverse and straight, with slight median notch; mandible striate-punctate; posterior margin of head straight or broadly rounded; antennal scape surpassing posterior cephalic margin; metanotal groove deeply impressed; promesonotum clearly convex; posterior margin of propodeum and petiole node rounded in profile, but truncate when viewed dorsally; anterior surface of third abdominal segment straight, not forming shallow cavity; integument covered with brownish slender hairs; larger species (HW: 1.63-1.8 mm); overall a smooth and glossy black ant.

Measurements (19 specimens): HW: 1.63-1.98, HL: 1.98-2.29, CI: 80-86, SL: 1.56-1.78, SI: 90-101, PW: 1.33-1.55, WL: 2.85-3.29, NL: 0.84-1.03, NW: 0.92-1.17, NH: 0.98-1.15, DNI: 105-118, LNI: 104-118.

Description: Head longer than broad, lateral borders convex from posterior margin to the level of eyes, then straight towards the base of mandibles; posterior margin broadly convex; head dorsum smooth and shiny between dense and very small punctures. Eyes large and strongly protruding from head capsule; with head in full-face view, eyes situated in anterior third of lateral cephalic margins. Antennal scape long, extending over posterior border of head; three most apical antennal segments almost the same width. Anterior margin of clypeus roughly straight and weakly medially notched. Mandibles striate, interspersed with punctures; outer margin gradually converging toward midline; masticatory margins with eight teeth or denticles.

With mesosoma in dorsal view, metanotal groove deeply impressed; in lateral view, dorsal outline of mesosoma not a continuous line, promesonotum and propodeum clearly convex and separated by a groove; declivitous surface convex, meeting the sides of propodeum at a blunt angle; lamellate membrane lacking on posterior margin of propodeum. Mesosoma dorsum smooth and shiny; mesopleuron, metapleuron, and anterior portion of the sides of propodeum with dense and small punctures. Petiole nodiform; about as long as broad in profile; subpetiolar process at a posteriorly acute angle; in dorsal view anterior and posterior margins convex. Anterior face of first gastral segment straight, without shallow impression to lodge the petiole node. Gastral tergites generally smooth and shiny dorsally and covered with dense and fine punctures laterally.

Standing hairs slender and reduced in number, but frost-like or golden pubescence is abundant especially on appendages and lower portion of the sides of body. Body color black, with bluish reflection; appendages reddishblack and tip of gaster light brown.

Discussion: Of the several species with a deeply impressed metanotal groove and straight anterior clypeal margin, P. sikorae is the largest in size (HW 1.63-1.98, WL 2.85-3.29) in the group and most easily recognized by its smooth and shiny black integument, with bluish reflection, which is covered with golden pubescence.

Several winged queens of this species have been recorded across its distributional range. These queens are characterized by the presence of three ocelli, flight thoracic sclerites with shallowly impressed metanotal groove, and the presence of much denser erect hairs and pubescence on the body dorsum and appendages. Apart from these typical forms, their size looks apparently similar to that of the workers. Two colonies, collected from the PN Zahamena contained gamergates, which may function as a secondary reproductive (Peeters, pers. comm.).

Distribution and biology: Pachycondyla sikorae is an endemic, widespread species that is distributed across the humid forest habitats in eastern Madagascar and occurs at a wide range of altitudes, from lowlands to high mountains. In the north of the island, its distribution ranges from the RS Manongarivo in the west to the PN Marojejy in the east, down to the PN Zahamena in the central east, through the PN Ranomafana and down to the PN Andohahela in the south. It generally nests in rotten logs and dead branches on the forest floor. Worker specimens have been found foraging mostly on the ground and in the leaf litter, and rarely on low vegetation.

Additional material examined: Province Antsiranana: 9.2 km WSW Befingotra, RS Anjanaharibe-Sud, - 14.75, 49.4667, 1200 m, montane rainforest (B.L. Fisher) (CASC); Betaolana Forest, along Bekona River, -14.53, 49.4404, 880 m, rainforest (B.L. Fisher et al.) (CASC); F Ambato, 26.6 km 33° Ambanja, -13.4645, 48.5517, 150 m, rainforest (B.L. Fisher) (CASC); Makirovana Forest, -14.1707, 49.9541, 415 m, rainforest, (B.L. Fisher et al.) (CASC); Makirovana Forest, -14.1604, 49.9522, 550 m, rainforest (B.L. Fisher et al.) (CASC); PN Marojejy, Antranohofa, 26.6 km 31° NNE Andapa, 10.7 km 318° NW Manantenina, -14.4433, 49.7433, 1325 m, montane rainforest (B.L. Fisher) (CASC); PN Marojejy, Manantenina River, 27.6 km 35° NE Andapa, 9.6 km 327° NNW Manantenina, -14.435, 49.76, 775 m, rainforest (B.L. Fisher et al.) (CASC); PN Marojejy, Manantenina River, 28.0 km 38° NE Andapa, 8.2 km 333° NNW Manantenina, -14.4367, 49.775, 450 m, rainforest, (B.L. Fisher et al.) (CASC); RS Manongarivo, 12.8 km 228° SW Antanambao, -13.9767, 48.4233, 780 m, rainforest, (B.L. Fisher) (CASC); RS Analamerana, 16.7 km 123° Anivorano-Nord, -12.8047, 49.3738, 225 m, tropical dry forest (B.L.

Fisher) (CASC); SAVA Region, district of Sambava, Marojejy National Park, 5 km W of Manantenina village, 1st Camp site (Mantella), -14.4382, 49.774, 487 m, low altitude rainforest (Rin'Ha, Mike) (CASC); Province Fianarantsoa: 2 km W Andrambovato, along Tatamaly River, -21.5117, 47.41, 1075 m, montane rainforest (B.L. Fisher et al.) (CASC); 3 km W Ranomafana, near Ifandiana, -21.25, 47.4167, 950 m, rainforest (P.S. Ward) (PSWC); 43 km S Ambalavao, PN Andringitra, -22.2333, 47, 825 m, rainforest (B.L. Fisher) (CASC); 45 km S. Ambalavao, 785 m, rainforest (B.L. Fisher) (CASC); 9.0 km NE Ivohibe, -22.4267, 46.9383, 900 m, montane rainforest (B.L. Fisher) [Sylvain] (CASC); PN Ranomafana, (L. Bartolozzi, S. Tiati & C. Raharimina) (MCZC); PN Befotaka-Midongy, Papango 27.7 km S Midongy-Sud, Mount Papango, -23.8352, 46.9637, 940 m, rainforest (B.L. Fisher et al.) (CASC); PN Befotaka-Midongy, Papango 28.5 km S Midongy-Sud, Mount Papango, -23.8408, 46.9575, 1250 m, montane rainforest (B.L. Fisher et al.) (CASC); PN Ranomafana, Vatoharanana River, 4.1 km 231° SW Ranomafana, -21.29, 47.4333, 1100 m, montane rainforest (Fisher, Griswold et al.) (CASC); Province Mahajanga: RS Marotandrano, Marotandrano 48.3 km S Mandritsara, -16.2832, 48.8144, 865 m, transitional humid forest (B.L. Fisher et al.) (CASC); Province Toamasina: [Madagascar central.] (MHNG); [Madagascar, Museum Paris, Grandidier 1893] (MNHN); Ambatovy, 12.4 km NE Moramanga, -18.8394, 48.3084, 1080 m, montane rainforest (B.L. Fisher et al.) (CASC); FC Didy, -18.1983, 48.5783, 960 m, rainforest (H.J. Ratsirarson) (CASC); FC Sandranantitra, -18.0483, 49.0917, 450 m, rainforest (H.J. Ratsirarson) (CASC); Manakambahiny, near Vavatenina Forest, -17.4667, 49.35, (A. Pauly) (CASC); PN Andasibe-Mantadia, F de Mantadia, 25.7 km 248° Moramanga, -18.814, 48.4303, 1040 m, rainforest (F.N. Raharimalala, B. Blaimer) (CASC); PN Zahamena, - 17.7336, 48.7262, 950 m, rainforest (B.L. Fisher et al.) (CASC); PN Zahamena, Besaky River, -17.7524, 48.8532, 760 m, rainforest (B.L. Fisher et al.) (CASC); PN Zahamena, Onibe River, -17.7591, 48.8547, 780 m, rainforest (B.L. Fisher et al.) (CASC); RNI Betampona, Camp Vohitsivalana, 37.1 km 338° Toamasina, -17.8867, 49.2025, 520 m, rainforest (B.L. Fisher et al.) (CASC); RNI Betampona, Betampona 35.1 km NW Toamasina, -17.918, 49.2007, 500 m, rainforest (B.L. Fisher et al.) (CASC); Province Toliara: PN Andohahela, 10 km NW Enakara, - 24.5667, 46.8167, 420 m, rainforest (B.L. Fisher) (CASC); PN Andohahela, 10 km SSW Eminiminy, -24.75, 46.7667, 830 m, rainforest (P.S. Ward) (PSWC); PN Andohahela, 13 km NW Enakara, -24.5667, 46.8167, 900 m, rainforest (B.L. Fisher) (CASC); F Ivohibe 55 km N Tolagnaro, -24.569, 47.204, 200 m, rainforest (B.L. Fisher et al.) (CASC); PN Andohahela, Col de Tanatana, 33.3 km NW Tolagnaro, -24.7585, 46.8537, 275 m, rainforest (B.L. Fisher et al.) (CASC); PN Andohahela, Col du Sedro, 3.8 km 113° ESE Mahamavo, 37.6 km 341° NNW Tolagnaro, -24.7639, 46.7517, 900 m, montane rainforest (Fisher-Griswold Arthropod Team) (CASC).