Pheidole flavominuta

The species was collected between 355-520 m in elevation, in rainforest. Nests were located in rotten logs, and under rootmats on the ground.

Identification
Salata and Fisher (2020) - A member of the Pheidole sikorae species group. Minute species. Major: HL < 0.85 mm and WL < 0.65 mm; head in full-face view elongate, not widening posteriorly with posterior sides slightly convex, in lateral view sub-oval and elongate with slightly convex dorsal and ventral sides; body yellow; sides of head with moderately dense, short, suberect to erect pilosity; entire head distinctly sculptured but with smooth interspaces; scape, when laid back, reaching the midlength of head; inner hypostomal teeth distinct, moderate, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, approximately as high and wide as inner teeth; inner and outer hypostomal teeth moderately closely spaced and not connected by concavity; base of first gastral tergite smooth. Minor: HL < 0.45 mm and WL < 0.5 mm, scape, when laid back, reaching the posterior head margin, propodeal spines small and triangular; head relatively rectangular; body yellow; head predominantly smooth; mesosoma smooth.

Pheidole flavominuta belongs to the group of species characterised by small body size (major workers: HL < 1.05 mm, WL < 0.9 mm and minor workers HL < 0.5 mm, WL < 0.6 mm), head in major workers elongate and not widening posteriorly, minor workers with predominantly smooth and relatively rectangular head, and yellow to brown body colouration. The group includes four species: P. flavominuta, Pheidole nitidobruna, Pheidole mikros, and Pheidole beanka Distribution of P. flavominuta covers area north from Toamasina up to Antenina and doesn't overlap with other members of this group. Pheidole flavominuta strongly differs from other members of the group by having distinctly yellow body colouration in major and minor workers. Additionally, major workers have head, in lateral view, sub-oval and elongate with slightly convex dorsal and ventral sides, and first gastral tergite is entirely smooth. Minor workers of this species can be also separated by a short antennal scape which doesn't exceed the posterior head margin.

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Nomenclature

 * . Pheidole flavominuta Salata & Fisher, 2020: 61, figs. 29A–F, 63K, 65K (w.) MADAGASCAR.

Worker
Major (N = 5): HL: 0.76-0.83 (0.8); HW: 0.68-0.73 (0.71); SL: 0.39-0.41 (0.4); EL: 0.08-0.08 (0.08); WL: 0.61-0.66 (0.64); PSL: 0.1-0.13 (0.12); MTL: 0.33-0.36 (0.35); PNW: 0.36-0.4 (0.37); PTW: 0.09-0.1 (0.1); PPW: 0.17-0.19 (0.18); CI: 111.3-115.3 (113.0); SI: 53.7-58.7 (56.2); PSLI: 12.8-15.5 (14.5); PPI: 47.4-60.8 (54.6); PNI: 51.4-53.9 (52.6); MTI: 48.2-49.6 (49.0).

Head. In full-face view elongate, not widening posteriorly, with anterior and posterior sides slightly convex. In lateral view sub-oval and elongate; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with moderately dense, short, suberect to erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, longitudinal, and dense rugae and smooth to indistinctly rugulate interspaces, rugae directed slightly outward on posteromedial part; lateral sides with thick, dense, and irregular rugae, interspaces shiny and distinctly rugoreticulate. Occipital lobes with dense, irregular rugae and distinctly rugoreticulate interspaces. Area posterolateral from eyes with weaker sculpture, rugoreticulate. Gena with relatively sparse and thick longitudinal rugae and smooth 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, reaching the midlength of head; pilosity subdecumbent to erect. Inner hypostomal teeth distinct, moderate, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, approximately as high and wide as inner teeth; inner and outer hypostomal teeth moderately closely spaced and not connected by concavity. Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum steep, mesonotal process very indistinct, bulge-like; promesonotal groove absent; metanotal groove absent; propodeal spines moderately long, with wide base and acute apex; humeral area laterally weakly produced. Surface shiny; promesonotum predominantly smooth with very fine network of rugoreticulae; anepisternum, katepisternum, and propodeum with rugoreticulae denser and thicker. Pilosity moderately dense, moderately long, and erect. Petiole. Shiny with dense foveolae; node smooth to finely foveolate, triangular, with rounded and thick apex, in rear view node dorsoventrally 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, moderately short, and erect. Colour. Yellow.

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 (N = 5): HL: 0.42-0.44 (0.43); HW: 0.37-0.39 (0.38); SL: 0.34-0.36 (0.35); EL: 0.06-0.07 (0.06); WL: 0.46-0.49 (0.47); PSL: 0.05-0.07 (0.06); MTL: 0.25-0.28 (0.26); PNW: 0.23-0.26 (0.25); PTW: 0.05-0.07 (0.06); PPW: 0.09-0.11 (0.1); CI: 108.4-117.2 (114.8); SI: 88.2-95.7 (93.2); PSLI: 12.2-16.9 (14.6); PPI: 47.7-70.7 (63.8); PNI: 59.6-69.4 (66.4); MTI: 67.7-70.3 (69.0).

Head. Cephalic margin indistinctly concave to straight. Pilosity relatively dense, moderately long, decumbent to suberect. Sculpture shiny and smooth; lateral sides of frons with fine, sparse, longitudinal, and interrupted rugulae; vertex with indistinct, sparse, and transverse rugulae; antennal sockets with few thick, curved outward rugae and smooth interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, reaching the posterior head margin; pilosity dense, subdecumbent to erect. Mesosoma. In lateral view, promesonotum moderately high and short, arched; promesonotal groove absent; metanotal groove distinct; propodeal spines small and triangular. Sculpture shiny and smooth. Pilosity moderately sparse, moderately long, and erect. Gaster. With sparse, erect pilosity. Colour. Yellow, head and gaster slightly darker.

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; Toamasina; Réserve Spéciale Ambatovaky, Sandrangato river; -16.81745, 49.2925; alt. 400 m; 26 Feb 2010; B. L. Fisher et al. leg.; rainforest, under root mat on ground; BLF24911; CASENT0923272. Paratype. 1w.; same data as for holotype, CASENT0162186 (CASC).

Etymology
Latin for bright and small in reference to small body size and bright colouration.