Pachycondyla vohitravo Rakotonirina and Fisher

Rakotonirina, J. C. & Fisher, B. L., 2013, Revision of the Pachycondyla sikorae species-group (Hymenoptera: Formicidae) in Madagascar, Zootaxa 3683 (4), pp. 447-485 : 478-480

Pachycondyla vohitravo Rakotonirina and Fisher , sp. nov.

(Figures 3, 25, 64, 65, 66, 80)

Holotype worker, Madagascar, Toamasina, Montagne d'Anjanaharibe, 18.0 km 21° NNE Ambinanitelo, -15.1883, 49.615, 470 m, sifted litter (leaf mold, rotten wood), rainforest, 8-12 Mar 2003 (coll. Fisher, Griswold et al.), collection code BLF08002, specimen code CASENT0034499 (CASC).

Paratype: one worker with same data as holotype but with specimen code CASENT0034500 (CASC).

WORKER. Diagnosis: Anteromedian margin of clypeus generally convex; posterolateral margins of propodeum and petiole node with a series of sharp teeth or tubercles, dorsal face of node bluntly tuberculate; second gastral tergite reticulate punctate or densely and coarsely punctate interspersed with small punctures; first and second gastral tergites covered with abundant pubescence.

Measurements (12 specimens): HW: 1.14-1.50, HL: 1.22-1.69, CI: 88-96, SL: 0.88-1.31, SI: 75-88, PW: 0.85-1.13, WL: 1.64-2.17, NH: 0.77-1.11, NL: 0.55-0.80, NW: 0.72-0.93, DNI: 115-141, LNI: 129-143.

Description: Head more or less elongate to subquadrate and broadest at about midlength; the sides normally convex and gradually converging from level of eyes to base of mandibles; posterior margin slightly concave. Head capsule reticulate-rugulose, rims of rugulation high and sharp. Eyes small and protruding, maximum diameter about the same as or less than widest part of antennal scape. Antennal scape barely reaching posterior border of head. Anteromedian margin of clypeus convex, with very slight median notch. Mandibles smooth and shiny between sparse punctures; apical margin equipped with 9-12 teeth or denticles.

With mesosoma in dorsal view, metanotal groove absent, pronotum generally densely punctate to reticulate-punctate interspersed with sparse blunt tubercles; propodeum reticulate-rugulose. In profile posterolateral margin of propodeum bordered with series of denticles or tubercles; mesopleural suture indistinct. With petiole in dorsal view, node roughly longer than broad; dorsum with scattered tubercles and small punctures, the spaces between which are smooth and shiny. In profile, petiolar node higher than long; lower half of posterior margin covered with a line of sharp teeth or denticles; subpetiolar process a simple anterior hooklike shape followed by small lobe posteriorly. Anterior face of first gastral segment straight, without shallow impression to lodge the petiolar node. Second gastral tergite reticulate punctate to densely punctate interspersed with small punctures.

Standing hairs present and pubescence abundant on dorsum of head and body; pubescence particularly abundant on first and second gastral tergites. Head, mesosoma, and petiole node dark brown to reddish-brown in color; gaster and appendages brown or of lighter coloration.

Discussion: Samples of P. vohitravo came from three isolated montane rainforest habitats, and each population shows a striking morphological divergence that might indicate several species are involved. This character variation include overall body size, the shape of the sides of the head, the presence or absence of a blunt angle on the middle of the convex anteromedial clypeal margin, and the strength of body sculpture. However, gradations in body size and sculpture also appear among populations within the distributional range of the species and we consider them to belong to a single variable species.

Pachycondyla vohitravo may be confounded with P. antsiraka and P. tahary , but the presence of abundant pubescence on the first and second gastral tergites render it separable from both. Its first and second gastral segments also have dense punctures, the spaces between which are less or about the same as their maximum diameter. For P. antsiraka and P. tahary , the distance between two punctures on first and second gastral segments is twice as long as the maximum diameter of the punctures.

Queen: unknown.

Distribution and biology: Pachycondyla vohitravo is known to occupy the disjunct mountain tops of the RS Anjanaharibe-Sud and Makira Forest in the north east of Madagascar, Andranomay Forest in the high plateau and the complex humid forests of Ambatovy-Analamay in the central eastern of the island (Fig. 80). Workers of P. vohitravo have been collected through leaf litter sampling, but one colony was collected from a rotten log.

Additional material examined: Province Antananarivo: 3 km 41° NE Andranomay, 11.5 km 147° SSE Anjozorobe, -18.4733, 47.96, 1300 m, montane rainforest (Fisher, Griswold et al.) (CASC); Province Antsiranana: RS Anjanaharibe-Sud, 9.2 km WSW Befingotra, -14.75, 49.4667, 1200 m, montane rainforest (B.L. Fisher) (CASC); Province Toamasina: Ambatovy, 12.4 km NE Moramanga, -18.8394, 48.3084, 1080 m, montane rainforest (B.L. Fisher et al.) (CASC); F Ambatovy, 14.3 km 57° Moramanga, -18.85083, 48.32, 1075 m, montane rainforest, (Malagasy ant team) (CASC); Torotorofotsy,-18.8708, 48.3474, 1070 m, montane rainforest, marsh edge, (Malagasy ant team) (CASC).