Pheidole dasos

The species was collected between 225-415 m in elevation, in rainforest. Nests were located in rotten logs.

Identification
Salata and Fisher (2020) - A member of the Pheidole sikorae species group. Moderately large species. Major: Head in full-face view sub-oval, not widening posteriorly, with anterior and posterior sides relatively straight, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with moderately dense, moderately long, subdecumbent to suberect pilosity; medial part of frons with thick, interrupted, sparse, and longitudinal rugae with indistinctly foveolate interspaces; anterolateral sides of frons with sparse, thick, and longitudinal rugae, posterolateral sides with rugae more irregular, interspaces with sparse foveolae; occipital lobes, and area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, narrower, and approximately as high as inner teeth; inner and outer hypostomal teeth closely spaced and not connected by concavity; mesosoma rugofoveolate; dorsal promesonotum with additional thick and transverse rugae; lateral sides of pronotum with smooth notches; gaster smooth; body orange. Minor: Head foveolate; vertex and median frons with fading sculpture; area posterolateral from eyes smooth; antennal sockets with few indistinct, curved outward rugae and foveolate interspaces; scape, when laid back, exceeding the posterior head margin by one-third of its length; promesonotum low and moderately long; promesonotal groove absent; propodeal spines small and triangular; mesosoma predominantly smooth; lateral sides with very sparse and indistinct, thin rugulae; body brown.

Pheidole dasos, described from Makirovana forest in Antsiranana, is most similar to Pheidole hazo, known from the vicinity of Andranoma in Antananarivo, and Pheidole sparsa, recorded so far only from Bemanevika in Mahajanga. Majors of P. dasos can be distinguished from both taxa by medial part of frons with moderately dense rugae with interspaces with indistinct foveolae, and pronotum predominantly sculptured with smooth notches on lateral sides; minors of P. dasos can be distinguished from P. sparsa and P. hazo by brown body colouration, longer scape exceeding the posterior head margin by one-third of its length, and predominantly smooth mesosoma with very sparse and indistinct, thin rugulae on lateral sides.

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Nomenclature

 * . Pheidole dasos Salata & Fisher, 2020: 58, figs. 28A–F, 63J, 65J (w.) MADAGASCAR.

Worker
Major (N = 2): HL: 1.1, 1.14; HW: 1.04, 1.12; SL: 0.79, 0.81; EL: 0.16, 0.14; WL: 0.98, 1.05; PSL: 0.14, 0.15; MTL: 0.72, 0.77; PNW: 0.4, 0.45; PTW: 0.13, 0.13; PPW: 0.29, 0.31; CI: 105.9, 101.4; SI: 76.2, 72.6; PSLI: 12.4, 13.5; PPI: 45.8, 41.7; PNI: 38.8, 39.9; MTI: 68.8, 68.6.

Head. In full-face view sub-oval, not widening posteriorly, with anterior and posterior sides relatively straight. In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with moderately dense, moderately long, subdecumbent to suberect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, interrupted, sparse, and longitudinal rugae with indistinctly foveolate interspaces; anterolateral sides of frons with sparse, thick, and longitudinal rugae, posterolateral sides with rugae more irregular, interspaces with sparse foveolae. Occipital lobes with slightly thinner, sparse, and irregular rugae and smooth to indistinctly foveolate interspaces. Area posterolateral from eyes with denser and thinner longitudinal rugae with rugofoveolate interspaces. Gena with relatively sparse and thick, longitudinal rugae with distinctly rugofoveolate interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina absent; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by two-fifths of its length; pilosity subdecumbent to erect. Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, narrower than and approximately as high as inner teeth; inner and outer hypostomal teeth closely spaced and not connected by concavity. Mesosoma. In lateral view, promesonotum short, angular and moderately low, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove absent; propodeal spines short, with wide base and acute apex; humeral area produced. Surface shiny and rugofoveolate; dorsal promesonotum with additional thick and transverse rugae; lateral sides of pronotum with smooth notches. Pilosity moderately dense, long, and erect. Petiole. Shiny with dense foveolae; node finely foveolate, triangular, with rounded and thick apex, in rear view node dorsoventrally slightly convex; pilosity moderately sparse and erect. Postpetiole. Shiny and foveolate; dorsum with reduced sculpture and smooth notch; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse and erect. Gaster. Shiny and smooth; pilosity moderately dense, long and erect. Colour. Orange with yellowish legs.

The following characters are found in most Pheidole sikorae species-group majors in Madagascar (Salata and Fisher 2020b). These characters also occur in , except for any differences noted in the paragraph above. Dorsal face of head in lateral view not depressed posteriorly; 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 absent; promesonotum strongly convex, well above the level of propodeum; petiolar peduncle with small horizontal lobes on its basal part; postpetiole short with slightly convex dorsum; petiolar peduncle without horizontal lobes on its basal part; body unicolourous.

Minor: Measurements (N = 2): HL: 0.56, 0.61; HW: 0.46, 0.49; SL: 0.71, 0.74; EL: 0.1, 0.1; WL: 0.74, 0.79; PSL: 0.08, 0.09; MTL: 0.57, 0.59; PNW: 0.31, 0.32; PTW: 0.09, 0.07; PPW: 0.12, 0.14; CI: 122.0, 122.7; SI: 153.6, 150.9; PSLI: 13.8, 15.4; PPI: 74.3, 52.9; PNI: 67.5, 65.7; MTI: 123.3, 120.5.

Head. Cephalic margin slightly convex. Pilosity relatively sparse, moderately long, subdecumbent to erect. Sculpture shiny and foveolate; vertex and median frons with fading sculpture; area posterolateral from eyes smooth; antennal sockets with few indistinct, curved outward rugae and foveolate interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, exceeding the posterior head margin by one-third of its length; pilosity dense, subdecumbent to erect. Mesosoma. In lateral view, promesonotum low and moderately long, arched; promesonotal groove absent; metanotal groove distinct; propodeal spines small, triangular. Sculpture shiny and predominantly smooth; lateral sides with very sparse and indistinct, thin rugulae. Pilosity very sparse, moderately long, and erect. Gaster. With sparse, erect pilosity. Colour. Brown, legs and gaster brighter.

The following characters are found in most Pheidole sikorae species-group minors in Madagascar (Salata and Fisher 2020b). These characters also occur in , except for any differences noted in the paragraph above. Antennal sockets shallow; frontal lobes absent; occipital carina 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, with node moderately low, triangular, and small, with few short, erect setae; petiolar peduncle with ventral face slightly convex; postpetiole smooth, short, low, and slightly convex, with few short, erect setae; gaster smooth and shiny; body unicolourous.

Type material
Holotype. Madagascar. 1 major worker; Antsiranana; Makirovana forest; -14.104, 50.03574; alt. 225 m; 4 May 2011; B. L. Fisher et al. leg.; rainforest, ex rotten log; BLF27046; CASENT0212441. Paratype. 1w.; same data as for holotype, CASENT0923284 (CASC).

Etymology
Greek for forest in reference to habitat preferences of the species.