Pheidole masoala

The species was collected between 30–520 m in elevation, in rainforest and disturbed rainforest. Nests were located in rotten logs and sticks on the ground.

Identification
Salata and Fisher (2020) - Major: Small species: HL: 0.93-1.17 (1.05), HW: 0.89-1.07 (0.97), WL: 0.76-0.92 (0.84); head in full-face view sub-rectangular, anterior and posterior sides of eyes relatively straight; sides of the head with sparse, moderately long, erect pilosity; antennal scrobes present, well delimited, and forming distinct dorsal concavity beneath frontal carina, scrobe surface foveolate, sometimes with additional sparse, thick, and irregular rugae, delimited ventrally and posteriorly by carinulae; inner hypostomal teeth distinct, big, closely spaced, triangular, with rounded apex and wide base; outer hypostomal teeth smaller and thinner than inner hypostomal teeth, with moderately wide base, triangular; gaster finely shagreened; body dark yellow. Minor: Head foveolate, genae with reduced sculpture or partially smooth; promesonotum low, long, flat or slightly convex, with relatively convex posterior declivity; propodeal spines minute, indistinct; mesosoma foveolate, katepisternum smooth.

Pheidole masoala is most similar to Pheidole madinika. Major workers. Pheidole masoala differs from P. madinika in dark yellow body colouration, presence of shallow transverse depression between frons and occipital lobes, and well developed antennal scrobes which are delimited ventrally and posteriorly by carinulae. Minor workers. Pheidole masoala differs from P. madinika by relatively convex posterior declivity of promesonotum, and shallow and indistinct metanotal groove.

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Nomenclature

 *  masoala. Pheidole masoala Salata & Fisher, 2020: 208, figs. 77A–F, 85I, 87M (w.) MADAGASCAR.

Worker
Major (N = 10): HL: 0.93-1.17 (1.05); HW: 0.89-1.07 (0.97); SL: 0.41-0.49 (0.45); EL: 0.13-0.16 (0.14); WL: 0.76-0.92 (0.84); PSL: 0.14-0.18 (0.16); MTL: 0.44-0.5 (0.45); PNW: 0.53-0.62 (0.58); PTW: 0.13-0.18 (0.15); PPW: 0.37-0.48 (0.43); CI: 90.8-95.9 (93.1); SI: 45.4-49.3 (46.7); PSLI: 13.4-16.2 (15.0); PPI: 31.9-37.5 (34.9); PNI: 56.7-63.7 (59.3); MTI: 44.9-49.1 (46.7). Head. In full-face view sub-rectangular, anterior and posterior sides of eyes relatively straight. In lateral view sub-rectangular; ventral and dorsal faces relatively flat; dorsal face finely depressed posteriorly, forming indistinct transverse depression between frons and occipital lobes; inner hypostomal teeth visible. Sides of the head with sparse, moderately long, erect pilosity; whole head with moderately dense, short, suberect to erect pilosity. Head depressed posteriorly, forming shallow transverse depression between frons and occipital lobes. Antennal scrobes distinct and delimited by carinulae; scrobe surface foveolate, sometimes with additional sparse, thick, and irregular rugae, delimited ventrally and posteriorly by carinulae. Occipital lobes shiny, with thick, sparse, irregular rugae, interspaces smooth; frons with dense, thick, and longitudinal rugae, interspaces smooth, and with fine but distinct foveolae on the upper half of frons; malar area with dense, thick, longitudinal to irregular rugulae, interspaces smooth; genae shiny, smooth to finely foveolate. Centre of clypeus smooth and shiny, lateral sides with longitudinal rugae; median notch present, wide and indistinct; median longitudinal carina absent; lateral longitudinal carinae present. Scape, when laid back, slightly exceeding midlength of head; pilosity suberect to erect. Inner hypostomal teeth distinct, big, closely spaced, triangular, with rounded apex and wide base; outer hypostomal teeth smaller and thinner than inner hypostomal teeth, with moderately wide base, triangular. Mesosoma. In lateral view, promesonotum moderately long, relatively low, and evenly angular, tubercle-like projections absent; promesonotal groove absent; metanotal groove absent; propodeal spines small, triangular, with acute apex; humeral area laterally weakly produced. Surface shiny, with fine foveolae, additional sparse and thin rugae on promesonotal dorsum and sometimes propodeum, sculpture slightly weakening on lateral surfaces of pronotum; katepisternum smooth. Pilosity sparse, moderately long, and erect. Petiole. Shiny and foveolate; peduncle short, with distinct horizontal lobes on its basal part; node relatively low, triangular, with rounded apex, in rear view node straight; pilosity moderately sparse and erect. Postpetiole. Shiny, with fine and sparse foveolae, smooth on dorsum; in dorsal view sides with long, acute, and triangular projections; pilosity long, moderately dense, and erect. Petiole. Shiny and finely shagreened; pilosity dense, moderately long, and erect. Colour. Unicolourous, dark yellow; lower part of malar area, frons, and gaster 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: 0.44-0.48 (0.46); HW: 0.39-0.43 (0.42); SL: 0.39-0.42 (0.4); EL: 0.09-0.1 (0.1); WL: 0.52-0.56 (0.54); PSL: 0.06-0.08 (0.07); MTL: 0.3-0.34 (0.32); PNW: 0.27-0.29 (0.27); PTW: 0.05-0.07 (0.06); PPW: 0.1-0.11 (0.1); CI: 88.5-95.2 (91.4); SI: 93.9-99.5 (97.3); PSLI: 13.3-16.5 (14.7); PPI: 50.5-64.6 (57.9); PNI: 63.8-68.5 (65.9); MTI: 73.4-80.0 (76.2). Head. Occipital margin straight or indistinctly concave; occipital carina absent. Pilosity moderately sparse, long, erect. Head foveolate, genae with reduced sculpture or partially smooth. Clypeus foveolate; 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 suberect. Mesosoma. In lateral view, promesonotum low, long, flat or slightly convex, with relatively convex posterior declivity; promesonotal groove absent; metanotal groove indistinct; propodeal spines minute, indistinct, triangular, apex acute. Sculpture foveolate, katepisternum smooth. Pilosity moderately sparse, moderately short, and erect. Petiole. Peduncle very short and thin with ventral face slightly convex; with few short, erect setae. Postpetiole. Short, low, and slightly convex; with few short, erect setae. Petiole. With 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; Antsiranana; Masoala National Park; -15.32331, 50.30751; alt. 60 m; 12 Mar 2014; B.L. Fisher et al. leg.; BLF32969, CASENT0375363. Paratype. Madagascar. 1w.; same data as for holotype; CASENT0923165 (CASC).

Etymology
From the type locality.