Pheidole kely

The species was collected between 325-990 m in elevation, in rainforest and Uapaca woodland. Nests were located in rotten logs, under rootmats, and under stones.

Identification
Salata and Fisher (2020) - A member of the Pheidole sikorae species group. Minute species. Major: HL < 1.0 mm and WL < 0.8 mm; head in full-face view sub-oval, widening slightly posteriorly, with anterior and posterior sides convex, in lateral view sub-oval; ventral and dorsal faces convex; body yellowish orange; sides of head with moderately dense, moderately long, suberect to erect pilosity; entire head distinctly sculptured, medial part of frons with thick, dense, longitudinal, and interrupted rugae and smooth to indistinctly rugulate interspaces; scape, when laid back, slightly exceeding the midlength of head; mesosoma with fine and sparse rugofoveolae, pronotum with rugofoveolae reduced and smooth notches on medial parts of dorsum and lateral sides; katepisternum with smooth notch; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, lower than inner teeth and approximately the same weight; inner and outer hypostomal teeth moderately closely spaced and not connected by concavity; base of first gastral tergite smooth. Minor: HL < 0.5 mm and WL < 0.6 mm, scape, when laid back, surpassing the posterior head margin by one-fifth of its length; propodeal spines small and triangular; head relatively rectangular; body dark yellow; head foveolate; medial side of frons with sparse, fine, and interrupted rugulae; area posterolateral from eyes smooth; mesosoma smooth.

Pheidole kely 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), sub-oval, slightly widening posteriorly head with anterior and posterior sides convex in major workers, and minor workers with yellow to brown body colouration and foveolate head or head predominantly smooth and relatively oval. The group includes six species: Pheidole havoana, P. kely, Pheidole parvula, Pheidole parvulogibba, Pheidole volontany, and Pheidole midongy. Pheidole kely is distributed from Toamasina north to Sambava and has a single record from Parc National d'Isalo in Fianarantsoa. Morphologically it is most similar to P. havoana and P. parvulogibba, described from the Anosyenne Mts. in Toliara, and parapatric P. parvula, known from two localities in the vicinity of Antananarivo. Minor workers of P. kely distinctly differ from those of P. parvula and P. parvulogibba in having a predominantly foveolate head. Minor workers of P. havoana and P. kely are indistinguishable. Major workers of P. kely differ from P. havoana and P. parvula in medial part of frons with thick, dense, longitudinal, and interrupted rugae and smooth to indistinctly rugulate interspaces; from P. parvulogibba in mesosoma with fine and sparse rugofoveolae, pronotum with rugofoveolae reduced, and smooth notches on medial parts of dorsum and its lateral sides.

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Nomenclature

 * . Pheidole kely Salata & Fisher, 2020: 84, figs. 36A–F, 63R, 65R (w.) MADAGASCAR.

Worker
Major (N = 10): HL: 0.9-0.97 (0.93); HW: 0.87-0.95 (0.91); SL: 0.48-0.53 (0.5); EL: 0.1-0.13 (0.11); WL: 0.77-0.84 (0.8); PSL: 0.12-0.15 (0.14); MTL: 0.44-0.5 (0.47); PNW: 0.39-0.46 (0.43); PTW: 0.1-0.14 (0.12); PPW: 0.25-0.31 (0.28); CI: 100.2-104.6 (102.4); SI: 53.1-58.3 (55.0); PSLI: 13.2-15.7 (14.5); PPI: 38.7-48.6 (41.8); PNI: 43.0-49.2 (47.3); MTI: 49.3-54.1 (51.5).

Head. In full-face view sub-oval, widening slightly posteriorly, with anterior and posterior sides convex. In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with moderately dense, moderately long, suberect to erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, dense, longitudinal, and interrupted rugae and smooth to indistinctly rugulate interspaces; lateral sides with thick, dense, and irregular rugae, interspaces shiny and distinctly rugofoveolate; rugae more longitudinal on anterolateral sides. Occipital lobes with thinner, irregular rugae and smooth to indistinctly rugofoveolate interspaces. Area posterolateral from eyes with sculpture weaker and rugoreticulate; sculpture weakening posteriorly. Gena with relatively sparse, thick, longitudinal rugae and smooth to indistinctly rugoreticulate interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina present; lateral longitudinal carinae absent. Scape, when laid back, slightly exceeding the midlength of head; pilosity subdecumbent to erect. Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, lower than inner teeth and approximately the same weight; 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 moderately steep, mesonotal process very indistinct, tubercle-like or absent; promesonotal groove absent; metanotal groove absent; propodeal spines moderately long, with moderately wide base and acute apex; humeral area laterally weakly produced. Surface shiny with fine and sparse rugofoveolae; pronotum with rugofoveolae reduced and smooth notches on medial parts of dorsum and lateral sides; katepisternum with smooth notch. Pilosity moderately sparse, long, and erect. Petiole. Shiny with fine foveolae; node smooth to finely foveolate, triangular, with rounded and thick apex, in rear view node dorsoventrally straight to 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 dense, moderately long, and erect. Colour. Yellowish orange; mandibles and gaster brown.

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 = 10): HL: 0.47-0.52 (0.49); HW: 0.4-0.45 (0.42); SL: 0.43-0.48 (0.45); EL: 0.09-0.11 (0.1); WL: 0.53-0.61 (0.57); PSL: 0.04-0.06 (0.05); MTL: 0.33-0.41 (0.37); PNW: 0.27-0.3 (0.28); PTW: 0.05-0.08 (0.06); PPW: 0.1-0.14 (0.12); CI: 111.9-121.1 (117.0); SI: 103.9-108.0 (106.1); PSLI: 7.9-11.7 (10.3); PPI: 48.3-64.2 (55.5); PNI: 64.9-69.7 (67.0); MTI: 80.2-98.8 (85.4).

Head. Cephalic margin indistinctly concave to straight. Pilosity relatively dense, moderately long, decumbent to suberect. Sculpture shiny and foveolate; medial side of frons with sparse, fine, and interrupted rugulae; area posterolateral from eyes smooth; antennal sockets with few thick, curved outward rugae and indistinctly foveolate interspaces. Clypeus with 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 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. Dark yellow, gaster and vertex brown.

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; Parc National de Zahamena; -17.73359, 48.72625; alt. 950 m; 19 Feb 2009; B. L. Fisher et al. leg.; rainforest, ex rotten log; BLF22067; CASENT0235022. Paratype. 1w.; same data as for holotype, CASENT0149839 (CASC).

Etymology
Malagasy for small in reference to body size.