Holotype. Madagascar. • 1 major worker; Antsiranana; Parc National de Marojejy, Antranohofa, 26.6 km 31°NNE Andapa, 10.7 km 318°NW Manantenina; -14.44333, 49.74333; alt. 1325 m; 20 Nov 2003; B. L. Fisher et al. leg.; montane rainforest, ex root mat, ground layer; BLF09196; CASENT0923295, top specimen on the pin (CASC). Paratypes. • 3w., 2s; same data as for holotype; CASENT0923294, CASENT0499827CASENT0499829 (CASC, MHNG, PBZT).

Madagascar. –Antsiranana: •1w., 1q.; Parc National de Marojejy, Antranohofa, 26.6 km 31°NNE Andapa, 10.7 km 318°NW Manantenina; -14.44333, 49.74333; alt. 1325 m; 20 Nov 2003; B. L. Fisher et al. leg.; montane rainforest, ex rotten tree stump; BLF09202 (CASC). •1w., 1s.; Parc National de Marojejy, Antranohofa, 26.6 km 31°NNE Andapa, 10.7 km 318°NW Manantenina; -14.44333, 49.74333; alt. 1325 m; 20 Nov 2003; B. L. Fisher et al. leg.; montane rainforest, ex rotten log; BLF09215 (CASC).

Moderately large species. Major workers. Head in full-face view sub-oval, widening posteriorly, with anterior and posterior sides convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with dense, short, suberect pilosity; anterior and medial parts of frons with moderately dense and thick, longitudinal and sometimes interrupted rugae with distinctly rugofoveolate interspaces; posterolateral sides with longitudinally irregular and thick rugae with distinctly rugofoveolate interspaces, area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by approximately one-fifth of its length; inner hypostomal teeth distinct, moderately long, closely spaced, triangular, with rounded apex and wide base; outer hypostomal teeth lobe-like, wider and higher than inner hypostomal teeth, apex directed outward; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity; promesonotum predominantly rugofoveolate, with additional sparse, thin, transverse rugae on pronotum; propodeum with fine rugofoveolae; gaster smooth; body yellowish orange. Minor workers. Head foveolate with additional indistinct rugulae on frons and vertex, area posterolateral from eyes with reduced sculpture, on posterior part predominantly smooth; scape, when laid back, surpassing the posterior head margin by two-fifths of its length; promesonotum moderately high and short; promesonotal groove present; propodeal spines indistinct, triangular; mesosoma smooth and shiny, only dorsum with few transverse, indistinct rugulae and propodeum with indistinct and sparse foveolae; body dark yellow.

Major workers. Measurements (N = 4): HL: 1.18–1.23 (1.21); HW: 1.21–1.27 (1.24); SL: 0.67–0.7 (0.69); EL: 0.14–0.16 (0.15); WL: 1.1–1.13 (1.12); PSL: 0.2–0.21 (0.2); MTL: 0.7–0.73 (0.72); PNW: 0.54–0.59 (0.57); PTW: 0.15–0.17 (0.16); PPW: 0.33–0.35 (0.34); CI: 96.7–97.8 (97.3); SI: 54.1–57.8 (55.4); PSLI: 16.3–17.7 (16.9); PPI: 43.4–50.5 (46.6); PNI: 43.9–46.9 (45.6); MTI: 56.7–58.8 (57.6).

Head. In full-face view sub-oval, widening posteriorly, with anterior and posterior sides convex (Fig. 25B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth invisible. Sides of the head with dense, short, suberect pilosity; whole head with relatively dense, short, decumbent to erect pilosity. Anterior and medial parts of frons with moderately dense and thick, longitudinal and sometimes interrupted rugae with distinctly rugofoveolate interspaces; posterolateral sides with longitudinally irregular and thick rugae with distinctly rugofoveolate interspaces. Occipital lobes with thick, sparse, irregular rugae, interspaces smooth or with fine, indistinct rugofoveolae. Gena with sparse and thick, longitudinal rugae and smooth interspaces. Area posterolateral from eyes with thin, longitudinal rugae with distinctly rugofoveolate interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, wide and shallow; median longitudinal carina absent; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by approximately one-fifth of its length; pilosity decumbent to suberect (Fig. 25B, D). Inner hypostomal teeth distinct, moderate, closely spaced, triangular, with rounded apex and wide base; outer hypostomal teeth lobe-like, wider and higher than inner hypostomal teeth, apex directed outward; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity (Fig. 63G). Mesosoma. In lateral view, promesonotum short, angular, and moderately high, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove absent; propodeal spines moderate, thin, with acute apex; humeral area laterally weakly produced (Fig. 25D). Surface shiny, promesonotum predominantly rugofoveolate, with additional sparse, thin, transverse rugae on pronotum; propodeum with fine rugofoveolae. Pilosity sparse, moderately long, and erect (Fig. 25D, F). Petiole. Shiny with fine and sparse rugofoveolae; node smooth to indistinctly rugulose, low, triangular, with rounded apex, in rear view node dorsoventrally convex; pilosity moderately sparse and erect (Fig. 25D, F). Postpetiole. Shiny, with fine and sparse rugulae; in dorsal view postpetiole oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect (Fig. 25D, F). Gaster. Shiny and smooth; pilosity sparse, long, and erect (Fig. 25D, F). Colour. Yellowish orange; mandibles and anterior part of head slightly darker (Fig. 25D, F).

Minor workers. Measurements (N = 9): HL: 0.57–0.64 (0.59); HW: 0.47–0.53 (0.5); SL: 0.59–0.66 (0.62); EL: 0.09–0.11 (0.1); WL: 0.7–0.79 (0.74); PSL: 0.06–0.08 (0.07); MTL: 0.48–0.56 (0.52); PNW: 0.3–0.38 (0.33); PTW: 0.07–0.1 (0.09); PPW: 0.13–0.16 (0.14); CI: 112.2–122.3 (119.5); SI: 121.6–130.3 (125.5); PSLI: 10.8–12.6 (11.8); PPI: 51.1–70.3 (61.2); PNI: 64.0–70.2 (66.2); MTI: 101.9–108.0 (104.8).

Head. Cephalic margin indistinctly convex (Fig. 25A). Pilosity relatively sparse, long, and subdecumbent. Head foveolate with additional indistinct rugulae on frons and vertex, area posterolateral from eyes with reduced sculpture and partially 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, surpassing the posterior head margin by two-fifths of its length; pilosity dense, subdecumbent to erect (Fig. 25A, C). Mesosoma. In lateral view, promesonotum moderately high, short, arched; promesonotal groove present, distinct; metanotal groove present and distinct; propodeal spines indistinct, triangular, apex acute (Fig. 25C). Sculpture smooth and shiny, only dorsum with few transverse, indistinct rugulae and propodeum with indistinct and sparse foveolae. Pilosity sparse, moderately long, and erect (Fig. 25C, E). Petiole. Peduncle with ventral face relatively straight; node low, knobbed, and small; with few short, erect setae (Fig. 25C, E). Gaster. With sparse, erect pilosity (Fig. 25C, E). Colour. Dark yellow (Fig. 25C, E).

From the type locality.

The species was collected at 1325 m in elevation, in montane rainforest. Nests were located in rotten logs, root mat and rotten tree stump.

Pheidole antranohofa sp. nov. is known only from its type locality: Parc National de Marojejy in Antsiranana. Morphologically it is most similar to P. sikorae Forel which is widely distributed from Forêt Ambohidena in Toamasina to Andrambovato in Fianarantsoa. Major workers of P. antranohofa sp. nov. can be distinguished based on developed sculpture of mesosoma, absence of impressed and smooth concavity placed lateral to antennal socket and tentorial pit and distinctly rugofoveolate interspaces on frons. However, minors of P. antranohofa sp. nov. and P. sikorae are indistinguishable.