Pachycondyla antsiraka Rakotonirina and Fisher

Rakotonirina, Jean Claude & Fisher, Brian L., 2013, Revision of the Pachycondyla sikorae species-group (Hymenoptera: Formicidae) in Madagascar, Zootaxa 3683 (4), pp. 447-485 : 459-461

Pachycondyla antsiraka Rakotonirina and Fisher , sp. nov.

( Figures 26 , 31, 32, 33 , 71 )

Holotype worker: Madagascar, Toamasina, FC Sandranantitra , -18.0483, 49.0917, 450 m, rainforest, sifted litter, 18–21 Jan 1999 (H.J. Ratsirarson) collection code: HJR101, specimen code: CASENT0317590 ( CASC).

Paratype: worker with same data as holotype but with specimen code HJR101 (3)–21 ( CASC).

WORKER. Diagnosis: Anterior margin of clypeus medially convex or with blunt angle; posterolateral margins of propodeum and petiolar node armed with a series of sharp teeth or tubercles; head densely and finely reticulaterugulose or reticulate-punctate behind the eye; with head in full face view, lateral borders anteriorly gradually curving towards the base of mandibles; in profile, distance between eyes and base of mandibles roughly three times or more the maximum diameter of eye; mesopleural sulcus distinctly continuous and narrowly impressed; second gastral tergite punctate, pubescence absent or reduced on first and second gastral segments.

Measurements (9 specimens): HW: 1.03–1.25, HL: 1.16–1.30, CI: 88–96, SL: 0.78–0.94, SI: 74–78, PW: 0.75–0.91, WL: 1.49–1.82, NH: 0.68–0.86, NL: 0.50–0.68, NW: 0.64–0.86, DNI: 125–141, LNI: 123–143.

Description: Head rectangular, with almost straight lateral margins which weakly converge to the base of the mandibles; posterior border more or less straight. Head capsule densely and finely reticulate-rugulose to reticulatepunctate; space between punctures about the same or smaller than diameter of puncture. Eye small, slightly protruding from the head surface, with 13 or fewer ommatidia; distance between eyes and base of mandibles roughly three times or more the maximum diameter of eye. Antennal scape short, not attaining posterior cephalic margin. Anteromedian margin of clypeus convex or bluntly angulate. Mandibular surface with widely spaced punctulae, the spaces between which are smooth and shiny; apical margins with 8–9 teeth or denticles.

In dorsal view, metanotal groove absent; dorsum of mesosoma reticulate-rugulose, interspersed with punctures; sparse tubercles may be present on anterior portion of pronotum. In profile, mesopleural suture visible as a continuous transverse sulcus from anterior margin to posterior border of mesopleuron. Posterior margin of propodeum with a sequence of teeth or denticles. In dorsal view, petiolar node punctate, lateral surface tuberculate, superimposed with punctures; in lateral view posterolateral margin of petiolar node armed with a series of sharp teeth or tubercles. First gastral segment without impression on its anterior face. First two gastral tergites with punctate sculpture.

Pilosity present on dorsum of body; pubescence sparse on first and second gastral tergites. Body color dark brown to reddish brown; appendages lighter.

Queen: unknown.

Distribution and biology: Pachycondyla antsiraka is recorded only from the lowland and littoral forests of the central east of the Madagascar ( Fig. 71 ) and worker specimens have been found mostly from leaf litter. Due to the hypogaeic habits of workers, the biology of this species is poorly understood.

Additional material examined: Province Toamasina: FC Sandranantitra, 450 m, rainforest (H.J. Ratsirarson) ( CASC); RS Ambatovaky, Sandrangato River, -16.7727, 49.2655, 450 m, rainforest (B.L. Fisher et al.) ( CASC); RS Ambatovaky, Sandrangato River, -16.7633, 49.2669, 520 m, rainforest (B.L. Fisher et al.) ( CASC); RS Ambatovaky, Sandrangato River, -16.8175, 49.295, 360 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); Réserve Ambodiriana, 4.8 km 306° Manompana, along Manompana River, -16.6723, 49.7012, 125 m, rainforest (B.L. Fisher et al.) ( CASC); SF Tampolo, 10 km NNE Fenoarivo Atsinanana, -17.2825, 49.43, 10 m, littoral rainforest (B.L. Fisher) ( CASC); Parcelle E3 Tampolo, -17.281, 49.4301, 10 m, littoral forest ( Malagasy ant team) ( CASC).

Figures

FIGURES 26 – 27. Mesosoma in lateral view; Fig. 26: mesopleural suture distinctly continuous and narrowly impressed (CASENT 0317590); Fig. 27: mesopleural suture indistinct (CASENT 0162668: holotype).

FIGURES 31 – 33. Worker caste of Pachycondyla antsiraka: lateral and dorsal view of body and full-face view of head, holotype CASENT 0317590.

FIGURES 70 – 75. Distribution maps of the Pachycondyla sikorae species-group in Madagascar. Fig. 70: P. agnivo; Fig. 71: P. antsiraka; Fig. 72: P. daraina; Fig. 73: P. g o ro g o t a; Fig. 74: P. haratsingy (circle) and P. i v o l o (triangle); Fig. 75: P. maeva.