Pheidole volontany

The species was collected at 1300 m in elevation, in montane rainforest. Nests were located in rotten logs.

Identification
Salata and Fisher (2020) - Minute species. Major: HL < 1.05 mm and WL < 0.9 mm; head in full-face view sub-oval, slightly widening posteriorly, with anterior and posterior sides convex, in lateral view sub-oval; ventral and dorsal faces convex; body dark brown; sides of head with dense, very long, suberect to erect pilosity; entire head distinctly sculptured, medial part of frons with moderately dense, thick, longitudinal, and interrupted rugae, interspaces shiny and smooth; scape, when laid back, exceeding the midlength of head by one-fifth of its length; promesonotal dorsum with rugofoveolae and additional thick transverse to irregular rugae; lateral sides of pronotum, anepisternum, katepisternum, and propodeum with dense and moderately thick to thin rugoreticulae; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed slightly inward; outer hypostomal teeth lobe-like, wider than inner hypostomal teeth, and approximately the same height, apex directed outward; inner and outer hypostomal teeth closely spaced and 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 minute, triangular; head relatively oval, smooth, and shiny with a few short, longitudinal rugae on the anterolateral sides of head; body brown; mesosoma smooth, indistinct foveolae can occur on propodeal dorsum and lateral sides of pronotum.

Pheidole volontany 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, Pheidole kely, Pheidole parvula, Pheidole parvulogibba, P. volontany, and Pheidole midongy. Because of dark body colouration P. volontany, known from Fort Classée d'Analavelona in Toliara, is most similar to P. midongy, described form Parc National Befotaka-Midongy in Fianarantsoa. Major workers of P. volontany differ from P. midongy in frons with moderately dense, thick, longitudinal, and interrupted rugae with shiny and smooth interspaces, and sides of the head with dense, very long, suberect to erect pilosity; minor workers differ in predominantly smooth head and darker brown body colouration.

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Nomenclature

 * . Pheidole volontany Salata & Fisher, 2020: 172, figs. 61A–F, 64S, 67K (w.) MADAGASCAR.

Worker
Major (N = 10): HL: 0.91-1.05 (0.98); HW: 0.97-1.06 (1.02); SL: 0.55-0.6 (0.57); EL: 0.12-0.15 (0.14); WL: 0.82-0.87 (0.85); PSL: 0.13-0.18 (0.15); MTL: 0.51-0.56 (0.53); PNW: 0.43-0.5 (0.46); PTW: 0.14-0.16 (0.15); PPW: 0.26-0.34 (0.3); CI: 93.0-101.0 (96.2); SI: 51.4-61.6 (56.3); PSLI: 13.3-17.7 (14.9); PPI: 44.0-58.0 (50.2); PNI: 44.0-58.0 (50.2); MTI: 49.2-53.6 (51.9).

Head. In full-face view sub-oval, slightly widening 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 dense, very long, suberect to erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with moderately dense, thick, longitudinal and interrupted rugae, interspaces shiny and smooth; anterolateral sides with longitudinal, thick, and dense rugae; interspaces shiny with relatively dense and distinct rugofoveolae; posterolateral sides with thick, dense, and irregular rugae with relatively dense and distinct rugofoveolae. Occipital lobes with sparse, thick, and irregular rugae; interspaces rugofoveolate. Gena with relatively dense, thick, longitudinal rugae and rugofoveolate interspaces. Area posterolateral from eyes shiny, with dense, thick rugofoveolae and smooth 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, exceeding the midlength of head by one-fifth of its length; pilosity subdecumbent to erect. Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed slightly inward; outer hypostomal teeth lobe-like, wider than inner hypostomal teeth and approximately the same height, apex directed outward; inner and outer hypostomal teeth closely spaced and connected by concavity. Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like or absent; promesonotal groove absent; metanotal groove absent; propodeal spines moderately short, with wide base and acute apex; humeral area laterally weakly produced. Surface shiny; promesonotal dorsum with rugofoveolae and additional thick transverse to irregular rugae; lateral sides of pronotum, anepisternum, katepisternum, and propodeum with dense and moderately thick to thin rugoreticulae. Pilosity sparse, long, and erect. Petiole. Shiny with fine foveolae; node smooth to finely foveolate, low, triangular, with rounded and thin 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, long, and erect. Colour. Dark brown; legs and antennae 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 = 10): HL: 0.48-0.51 (0.5); HW: 0.44-0.46 (0.45); SL: 0.47-0.51 (0.49); EL: 0.09-0.11 (0.1); WL: 0.57-0.62 (0.59); PSL: 0.06-0.08 (0.07); MTL: 0.37-0.39 (0.38); PNW: 0.27-0.31 (0.29); PTW: 0.06-0.08 (0.07); PPW: 0.11-0.13 (0.12); CI: 108.8-116.0 (112.0); SI: 105.4-111.4 (108.4); PSLI: 11.2-14.6 (13.0); PPI: 56.9-70.2 (62.7); PNI: 61.4-68.6 (65.3); MTI: 81.3-88.2 (84.3).

Head. Cephalic margin indistinctly concave or straight. Pilosity relatively sparse, long, decumbent to suberect. Sculpture smooth and shiny with a few short, longitudinal rugae on the anterolateral sides of head; 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, 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 minute, triangular. Sculpture shiny and smooth; indistinct foveolae can occur on propodeal dorsum and lateral sides of pronotum. Pilosity very sparse, moderately long, and erect. Postpetiole. Short, low, and relatively flat; with few short, erect setae. Gaster. With sparse, erect pilosity. Colour. Brown, legs and antenna yellow.

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; Toliara; Fort Classée d'Analavelona, 33.2 km 344°NNW Mahaboboka; -22.64333, 44.17167; alt. 1300 m; 22 Feb 2003; Fisher et al. leg.; montane rainforest, ex rotten log; BLF07935; CASENT0491861, bottom specimen on the pin. Paratypes. 9w., 3s.; same data as for holotype; CASENT0491860, CASENT0491863, CASENT0491862, CASENT0491864, CASENT0872247 (CASC,, ).

Etymology
Malagasy for brown in reference to body colouration.