Pheidole ankerana

The species was collected between 725–865 m in elevation, in rainforest. Nests were located in rotten logs.

Identification
Salata and Fisher (2020) - Major: Head in full-face view rectangular, with lateral sides relatively straight, only posteriormost part slightly convex; sides of the head with dense, long, suberect pilosity; occipital lobes and genae shiny, with thick, sparse, irregular rugae; frons with sparse, thick, and longitudinal rugae, interspaces smooth; inner hypostomal teeth distinct, small, and low, closely spaced, lobe-like, with rounded apex and wide base; outer hypostomal teeth bigger and wider than inner hypostomal teeth, triangular; inner and outer teeth closely spaced and connected by concavity; propodeal spines moderately long, triangular, with acute apex; gaster smooth; body reddish brown. Minor:. Head foveolate with additional thin, sparse rugae on the whole surface; promesonotum low, short, slightly convex, with relatively steep posterior declivity; propodeal spines minute, triangular; mesosoma foveolate with additional thin, sparse rugae, katepisternum smooth.

Major workers. Pheidole ankerana is most similar to Pheidole vatovavensis. It differs from P. vatovavensis in denser and longer pilosity on the sides of head, smooth sculpture of interspaces on frons, sculpture of scrobes never foveolate, lower promesonotum and lobe-like shape of inner hypostomal teeth. Minor workers. Pheidole ankerana differs from P. vatovavensis by presence of additional thin, sparse rugae on the whole surface of head and mesosoma and minute size of propodeal spines.

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Nomenclature

 *  ankerana. Pheidole ankerana Salata & Fisher, 2020: 192, figs. 71A–F, 84D, 86D (w.q.) MADAGASCAR.

Worker
Major (N = 5): HL: 1.42-1.52 (1.48); HW: 1.34-1.43 (1.38); SL: 0.61-0.65 (0.63); EL: 0.16-0.2 (0.18); WL: 1.07-1.16 (1.12); PSL: 0.19-0.21 (0.2); MTL: 0.65-0.68 (0.66); PNW: 0.62-0.67 (0.64); PTW: 0.15-0.17 (0.16); PPW: 0.47-0.51 (0.49); CI: 92.1-94.1 (93.3); SI: 44.7-46.2 (45.5); PSLI: 12.1-14.6 (13.4); PPI: 28.9-32.7 (31.6); PNI: 45.7-47.5 (46.6); MTI: 47.4-48.8 (48.3). Head. In full-face view rectangular, with lateral sides relatively straight, only posteriormost part slightly convex. In lateral view sub-rectangular; ventral and dorsal faces finely convex; dorsal face finely depressed posteriorly, forming shallow transverse depression between frons and occipital lobes; inner hypostomal teeth invisible. Sides of the head with dense, long, suberect pilosity; whole head with dense, moderately long, suberect to erect pilosity. Antennal scrobes indistinct and not delimited by carinulae; scrobe surface shiny, with dense, thick, and irregular rugoreticulation. Occipital lobes and genae shiny, with thick, sparse, irregular rugae; frons with sparse, thick, and longitudinal rugae, interspaces smooth; malar area with dense, thick, and longitudinal rugae, interspaces smooth to finely rugulose. Centre of clypeus smooth and shiny, lateral sides with longitudinal rugae; median notch present, narrow and shallow to moderate; median longitudinal carina present; lateral longitudinal carinae absent. Scape, when laid back, slightly exceeding the midlength of head; pilosity decumbent to erect. Inner hypostomal teeth distinct, small and low, closely spaced, lobe-like, with rounded apex and wide base; outer hypostomal teeth bigger and wider than inner hypostomal teeth, triangular; inner and outer teeth closely spaced and connected by concavity. Mesosoma. In lateral view, promesonotum short, angular, and low, posterior mesonotum relatively steep, with indistinct tubercle-like projection; promesonotal groove absent; metanotal groove absent; propodeal spines moderately long, triangular, with acute apex; humeral area laterally weakly produced. Surface shiny, with fine to thin, dense rugoreticulation, sculpture weakening on dorsum, katepisternum smooth. Pilosity moderately sparse, long, and erect. Petiole. Shiny; peduncle shagreened, short, without horizontal lobes on its basal part; node smooth, relatively high and thin, triangular, with rounded apex, in rear view node straight; pilosity moderately sparse and erect. Postpetiole. Finely shagreened, shiny; in dorsal view sides with moderately short, acute, and horn-like projections; pilosity long, moderately sparse and erect. Petiole. Smooth; pilosity moderately dense, long, and erect. Colour. Unicolourous, reddish brown; legs dark yellow.

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 = 5): HL: 0.61-0.69 (0.66); HW: 0.55-0.63 (0.59); SL: 0.58-0.64 (0.61); EL: 0.11-0.13 (0.12); WL: 0.75-0.85 (0.8); PSL: 0.09-0.11 (0.1); MTL: 0.48-0.55 (0.51); PNW: 0.37-0.43 (0.4); PTW: 0.06-0.08 (0.07); PPW: 0.13-0.2 (0.16); CI: 88.5-93.8 (90.3); SI: 99.2-105.1 (102.4); PSLI: 14.4-17.3 (15.5); PPI: 38.2-52.7 (45.5); PNI: 66.1-68.6 (67.6); MTI: 79.5-90.1 (86.9). Head. Occipital margin straight or indistinctly concave; occipital carina indistinct, weakly developed. Pilosity moderately dense, long, erect. Whole head foveolate with additional thin, sparse rugae on the whole surface. Clypeus shiny, with sparse, irregular rugae; median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, surpassing the posterior head margin by one-fifth of its length; pilosity erect. Mesosoma. In lateral view, promesonotum low, short, slightly convex, with relatively steep posterior declivity; promesonotal groove absent; metanotal groove absent; propodeal spines minute, triangular, apex acute. Sculpture foveolate with additional thin, sparse rugae on the whole surface, katepisternum smooth. Pilosity sparse, long, and erect. Petiole. Peduncle short and thin; node moderately high, triangular and small; with few long, erect setae. Postpetiole. Short, low, and slightly convex; with few short, erect setae. Petiole. With moderately sparse, erect pilosity. Colour. Unicolourous, yellow.

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; Toamasina; Ankerana; -18.4104, 48.8189; alt. 855 m; 27 Jan 2012; B.L. Fisher et al. leg.; BLF28148, CASENT0923171. Paratypes. Madagascar. 2w., 1q.; same data as for holotype; CASENT0274002, CASENT0274003, CASENT0872185 (CASC).

Etymology
From the type locality.