Pheidole mahaboensis

The species was collected at between 20–1275 m in elevation, in rainforest and once in open area near stream. Nests were located in rotten logs and tree stumps.

Identification
Salata and Fisher (2020) - Major: Large species: HL: 2.38-2.71 (2.56), HW: 2.34-2.61 (2.48), WL: 1.78-1.96 (1.83); propodeal spines very long (PSL: 0.64-0.75 (0.7)); head in full-face view trapezoid, widened posteriorly; sides of the head with very sparse, short, decumbent pilosity; frons with longitudinal rugae reaching further than midlength of head; gaster smooth and shiny; body reddish brown to dark brown. Minor:. Large species: 0.93-1.08 (1.0), HW: 0.79-0.93 (0.88), WL: 1.2-1.5 (1.4); propodeal spines very long (PSL: 0.53-0.66 (0.61)); scape, when laid back, surpassing posterior head margin by more than half its length; pronotum and mesonotal dorsum shiny, smooth or with indistinct, sparse, superficial rugulae; anepisternum, katepisternum and propodeum shiny, with slightly denser superficial rugulae; promesonotal groove present; metanotal groove narrow and relatively deep.

This species is most similar to Pheidole longispinosa and Pheidole praegrandis. Major workers. Pheidole mahaboensis can be distinguished from P. longispinosa by presence of metanotal groove, presence of very sparse, short, decumbent pilosity at the sides of head, and longitudinal rugae reaching at least midlength of head; from P.  praegrandis by presence of metanotal groove, presence of very sparse, short, decumbent pilosity at the sides of head, and not shagreened first gastral tergite and head. Minor workers. Pheidole mahaboensis can be distinguished from P. longispinosa by presence of promesonotal groove, narrow and relatively deep metanotal groove, and presence of fine superficial rugulae on most of mesosoma; from P.  praegrandis by mostly smooth and shiny sculpture of head and mesosoma, which is never rugoreticulate.

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Nomenclature

 *  mahaboensis. Pheidole mahaboensis Salata & Fisher, 2020: 52, figs. 24A–F, 85B, 87F (w.m.) MADAGASCAR.

Worker
Major (N = 10): HL: 2.38-2.71 (2.56); HW: 2.34-2.61 (2.48); SL: 1.1-1.24 (1.16); EL: 0.22-0.28 (0.25); WL: 1.78-1.96 (1.83); PSL: 0.64-0.75 (0.7); MTL: 1.21-1.32 (1.27); PNW: 0.74-0.86 (0.8); PTW: 0.21-0.26 (0.24); PPW: 0.73-0.83 (0.77); CI: 93.0-101.0 (96.9); SI: 44.3-49.7 (46.6); PSLI: 25.5-29.6 (27.3); PPI: 27.8-33.7 (30.9); PNI: 30.1-35.6 (32.4); MTI: 49.8-53.5 (51.3). Head. In full-face view trapezoid, widened posteriorly. In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with very sparse, short, decumbent pilosity; frons and vertex with few additional, long, erect setae. Antennal scrobes absent or very indistinct. Occipital lobes smooth and shiny; genae smooth and shiny or dull, superficially rugulose with median shiny patch widening posteriorly; centre of frons shiny with longitudinal rugae reaching at least midlength of head, sometimes surface between rugae with superficial rugulae; malar area and lateral sides of head superficially rugulose, sometimes with several short, longitudinal rugae; posterior part of frons smooth and shiny or superficially rugulose; head sculpture weakens posteriorly. Centre of clypeus smooth and shiny, lateral sides superficially rugulose; median notch present, shallow, and wide; median longitudinal carina absent; lateral longitudinal carinae absent. Scape, when laid back, reaching midlength of head; pilosity decumbent to subdecumbent. Inner hypostomal teeth distinct, low, triangular, and thick, with rounded apex, closely spaced; outer hypostomal teeth distinct, slightly smaller and thinner than inner hypostomal teeth, lobe-like. Mesosoma. In lateral view, promesonotum low, short, and relatively flat; pronotum slightly convex; mesonotum slightly concave; posterior mesonotum relatively steep; promesonotal groove absent; metanotal groove narrow and relatively deep; propodeal spines very long, massive basally, with acute apex; humeral area laterally weakly or not produced. Surface shiny and smooth with weak, sparse, and irregular rugae on pronotum, lateral sides of propodeum, katepisternum, and anepisternum. Pilosity very sparse, short, and decumbent; dorsum with few additional, long erect setae. Petiole. Smooth and shiny; peduncle long and thin, superficially rugulose ventrally; node triangular with rounded apex, in rear view node dorsoventrally depressed; pilosity sparse, short, and erect. Postpetiole. Smooth and shiny; in dorsal view sides with acute, narrow, triangular projections; pilosity short to long, sparse, and erect. Gaster. Pilosity sparse, long, and erect. Colour. Unicolourous, reddish brown to dark brown.

Unless otherwise noted above, the following characters occur in this species, and the majority of Pheidole majors of Madagascar described by Salata and Fisher 2020a. Antennal sockets shallow; frontal lobes absent; head in full-face view with distinct median concavity; antenna 12-segmented, with 3-segmented club; masticatory margin of mandible with large, stout apical and preapical teeth, followed by a long diastema and then a short and crenulate tooth just before the rounded basal angle; outer surface of mandible mostly smooth and shining, sometimes with weak and sparse foveolae; antennal scrobes present; promesonotum strongly convex, well above the level of propodeum; postpetiole short with slightly convex dorsum; ventral process absent.

Minor (N = 10): HL: 0.93-1.08 (1.0); HW: 0.79-0.93 (0.88); SL: 1.16-1.32 (1.26); EL: 0.13-0.19 (0.16); WL: 1.2-1.5 (1.4); PSL: 0.53-0.66 (0.61); MTL: 0.96-1.11 (1.06); PNW: 0.53-0.68 (0.6); PTW: 0.12-0.13 (0.13); PPW: 0.19-0.22 (0.21); CI: 85.0-90.1 (87.4); SI: 141.5-146.5 (144.1); PSLI: 57.3-63.2 (60.5); PPI: 55.2-66.8 (61.8); PNI: 62.7-73.1 (68.3); MTI: 116.8-126.5 (120.8). Head. Occipital margin convex; occipital carina narrow, weakly developed. Pilosity sparse, short, and appressed on the whole surface and additionally long and erect on frons and median part of occiput. Sculpture smooth and shiny on the whole surface, only antennal sockets with sparse carinae curved outward. Clypeus smooth and shiny; its anterior margin regularly convex, with weakly developed teeth; median longitudinal carina absent; two lateral longitudinal carinae present. Scape, when laid back, surpassing posterior head margin by more than half of its length; pilosity suberect to erect. Mesosoma. In lateral view, promesonotum low, long, and slightly convex; promesonotal groove indistinct; metanotal groove narrow and relatively deep; propodeal spines very long, massive basally, with acute apex. Pronotum and mesonotal dorsum shiny, smooth or with indistinct, sparse, superficial rugulae; anepisternum, katepisternum, and propodeum shiny, with slightly denser superficial rugulae. Pilosity short, very sparse, suberect. Petiole. Peduncle long and thin; node bulge-like with rounded apex; pilosity absent. Postpetiole. Moderately long, low, and slightly convex; with two long, erect setae at the anterior edge. Gaster. With few long, erect setae. Colour. Unicolourous, brown to dark brown.

Unless otherwise noted above, the following characters occur in this species, and the majority of Pheidole minors of Madagascar described by Salata and Fisher 2020a. Antennal sockets shallow; frontal lobes absent; head in full-face view oval, posterior and anterior of eyes convex; antenna 12-segmented, with 3-segmented club; humeral area not developed; clypeus smooth and shiny; its anterior margin regularly convex; promesonotum well above the level of propodeum; petiole smooth; petiole with node moderately low, triangular and small postpetiole smooth; gaster smooth and shiny.

Type Material
Holotype. Madagascar. 1 major worker; Fianarantsoa; Réserve Forestière d’Agnalazaha, Mahabo, 42.9 km 215° Farafangana; -23.19383, 47.723; alt. 20 m; 19 Apr 2006; B.L. Fisher et al. leg.; BLF13900, CASENT0070925. Paratypes. Madagascar. 2w. 1m.; same data as for holotype; CASENT0872077, CASENT0070926, CASENT0872197 (CASC).

Etymology
From the type locality.