Pheidole litigiosa

The species was collected between 1317-1409 m in elevation. Biology unknown.

Identification
Salata and Fisher (2020) - Moderately large species. Major: Head in full-face view sub-oval and not widening posteriorly, with anterior and posterior sides slightly convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with moderately dense, short, subdecumbent to suberect pilosity; medial part of frons with thick, longitudinal, interrupted, and moderately dense rugae, interspaces rugulate; occipital lobes smooth and shiny; area posterolateral from eyes smooth and shiny; scape, when laid back, exceeding the midlength of head by one-fifth of its length; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth dentate, wider than and approximately as high as inner teeth; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity; promesonotum predominantly smooth with sparse and moderately thick, irregular to transverse rugae on lateral sides; anepisternum, katepisternum, and propodeum finely rugofoveolate; katepisternum with smooth notch; body yellowish orange. Minor: Head foveolate; vertex, area posterolateral from eyes smooth; scape, when laid back, exceeding the posterior head margin by one-fifth of its length; promesonotum moderately low and short; promesonotal groove present; propodeal spines small, triangular; mesosoma smooth; propodeum and sometimes katepisternum with sparse foveolae; body orange to yellow.

Pheidole litigiosa is a member of a group of species characterised by distinctly reduced head sculpture in major workers with occipital lobes entirely or predominantly smooth, area posterolateral from eyes partially or entirely smooth and shiny or with reduced sculpture and smooth notches. The group consists of four species: P. litigiosa, Pheidole masoandro, Pheidole gracilis, and Pheidole tampony. Pheidole litigiosa is the only member of this group known from the Antananarivo prefecture. Morphologically P. litigiosa is most similar to P. masoandro known from Anosyenne Mts. in Toliara. Its major workers can be separated based on medial part of frons with thick, longitudinal, interrupted, and moderately dense rugae with rugulate interspaces, moderately dense, short, subdecumbent to suberect pilosity on sides of the head, and having outer hypostomal teeth dentate, wider than and approximately as high as inner teeth; minor workers have indistinct promesonotal groove, propodeal spines small and triangular, and frons lacking additional, short rugae. Despite strong morphological differences in major workers, minor workers of P. litigiosa are extremely similar to those of Pheidole sikorae and Pheidole antranohofa and can be separated based on lack of additional, short rugae.

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar, Madagascar.

Worker
minor

Nomenclature

 *  litigiosa. Pheidole sikorae var. litigiosa Forel, 1892k: 526 (s.w.q.) MADAGASCAR.
 * Status as species: Salata & Fisher, 2020: 91.

Worker
Salata and Fisher (2020) - Major (N = 3): HL: 1.1-1.17 (1.12); HW: 1.02-1.11 (1.06); SL: 0.59-0.63 (0.61); EL: 0.12-0.13 (0.12); WL: 0.85-1.03 (0.95); PSL: 0.17-0.22 (0.19); MTL: 0.55-0.65 (0.6); PNW: 0.51-0.55 (0.53); PTW: 0.16-0.16 (0.16); PPW: 0.3-0.36 (0.33); CI: 105.0-107.2 (106.2); SI: 56.0-59.5 (57.7); PSLI: 15.7-18.6 (16.8); PPI: 42.9-52.4 (47.7); PNI: 49.0-52.4 (50.6); MTI: 52.6-58.5 (56.2).

Head. In full-face view sub-oval, not widening posteriorly, with anterior and posterior sides slightly convex. In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with moderately dense, short, subdecumbent to suberect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, longitudinal, interrupted, and moderately dense rugae, interspaces rugulate, rugae directed slightly outward on posteromedial part; lateral sides with thick, dense, and longitudinal rugae with distinctly rugulate interspaces, rugae more irregular on the posterolateral parts. Occipital lobes smooth and shiny. Area posterolateral from eyes smooth and shiny. Gena with relatively sparse and thick longitudinal rugae and smooth to indistinctly rugulate 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 one-fifth of its length; pilosity subdecumbent to erect. Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth dentate, wider than and approximately as high as inner teeth; inner and outer hypostomal teeth closely spaced and connected by indistinct 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 moderate, with moderately narrow base and acute apex; humeral area weakly produced. Surface shiny; promesonotum predominantly smooth with sparse and moderately thick, irregular to transverse rugae on lateral sides; anepisternum, katepisternum, and propodeum finely rugofoveolate; katepisternum with smooth notch. Pilosity moderately dense, long, and erect. Petiole. Shiny with sparse foveolae; node finely foveolate, triangular, with rounded and thick apex, in rear view node dorsoventrally slightly concave; 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 moderately large dentate projections; pilosity long, moderately sparse, and erect. Gaster. Shiny and smooth; pilosity moderately dense, moderately long, and erect. Colour. Yellowish orange with yellow 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 (N = 3): HL: 0.54-0.6 (0.57); HW: 0.46-0.52 (0.5); SL: 0.57-0.62 (0.59); EL: 0.09-0.1 (0.09); WL: 0.68-0.8 (0.73); PSL: 0.09-0.11 (0.1); MTL: 0.46-0.56 (0.5); PNW: 0.28-0.33 (0.31); PTW: 0.08-0.11 (0.1); PPW: 0.13-0.17 (0.15); CI: 112.7-118.1 (115.4); SI: 111.3-124.4 (118.3); PSLI: 15.3-18.9 (17.6); PPI: 61.3-69.6 (64.5); PNI: 54.6-68.1 (61.9); MTI: 88.2-107.1 (100.7).

Head. Cephalic margin relatively straight. Pilosity relatively sparse, moderately long, decumbent to subdecumbent. Sculpture shiny and foveolate; vertex, and area posterolateral from eyes smooth; antennal sockets with few thick, 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-fifth of its length; pilosity dense, suberect to erect. Mesosoma. In lateral view, promesonotum moderately low and short, arched; promesonotal groove present; metanotal groove distinct; propodeal spines small, triangular. Sculpture shiny and smooth; propodeum and sometimes katepisternum with sparse foveolae. Pilosity very sparse, moderately long, and erect. Gaster. With sparse, erect pilosity. Colour. Orange to 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
Salata and Fisher (2020) - Pheidole sikorae var. litigiosa Forel, 1892: 526 (s.w.q.). Lectotype [designated here]: major worker (top specimen, CASENT0101628): Madagascar, Antananarivo, Fort d'Andrangoloaka, coll. Sikora [examined]. Paralectotypes: 1 major worker (CASENT0923211) (MHNG) [examined], 1 minor worker (CASENT0923210) (MHNG) [examined], 1 queen (CASENT0101935) (MHNG) [examined], 1 worker (CASENT0101638) (MHNG) [examined].