Pheidole madecassa Forel, 1892

Salata, Sebastian & Fisher, Brian L., 2020, The ant genus Pheidole Westwood, 1839 (Hymenoptera: Formicidae) in Madagascar-taxonomic revision of the bessonii species-group, Zootaxa 4843 (1), pp. 1-64 : 36-38

Pheidole madecassa Forel, 1892

Figs 17 A–F, 27I, 28I

Pheidole madecassa Forel, 1892: 525 (s.w.)

LECTOTYPE: [designated here]:1s., bottom specimen on the pin, Madagascar, Toamasina, Mangoro river , coll. Sikora, CASENT0101707, ANTC3400 ( MHNG) . PARALECTOTYPES: 1s., top specimen, the same pin as lectotype, CASENT0876545, ANTC3400 ( MHNG); 2w. , the same data as lectotype, CASENT0101897, ANTC3401 ( MHNG) .

Other material. Madagascar. Antsiranana: 2w., 1s., 9.2 km WSW Befingotra, Rés. Anjanaharibe-Sud, -14.75 49.46667, 1180 m, B. L. Fisher et al. leg. ( CASC) ; 1w., 9.2 km WSW Befingotra, Rés. Anjanaharibe-Sud, -14.75, 49.46667 1200 m, B. L. Fisher et al. leg. ( CASC) . Toamasina: 3w., 1s., 6.9 km NE Ambanizana, Ambohitsitondroina , -15.58506 50.00952, 825 m, B. L. Fisher et al. leg. ( CASC) ; 6w., F.C. Didy , -18.19833 48.57833, 960 m, H. J. Ratsirarson leg. ( CASC) ; 1s., Forêt Ambatovy, 14.3 km 57° Moramanga , -18.85083 48.32, 1075 m, B. L. Fisher et al. leg. ( CASC) ; 2w., 1s., Reserve Betampona, Camp Vohitsivalana , 37.1 km 338 ° Toamasina, -17.88667 49.2025, 520 m, B. L. Fisher et al. leg. ( CASC) ; 1w., 2s., Réserve Spéciale Ambatovaky, Sandrangato river , -16.76912 49.26704, 475 m, B. L. Fisher et al. leg. ( CASC) ; 3w., Réserve Spéciale Ambatovaky, Sandrangato river , -16.80561 49.29507, 480 m, B. L. Fisher et al. leg. ( CASC) .

Geographic range. Madagascar, from Andapa in Antsiranana south to Moramanga in Toamasina.

Diagnosis. Major workers. Head in full-face view sub-rectangular, slightly widening posteriorly, with lateral margins slightly convex; side of head with dense, long, subdecumbent to suberect pilosity; antennal scrobes very indistinct with sparse and very thin rugocostulae; interspaces between rugocostulae smooth; frons with sparse and thin costulae; interspaces between costulae smooth; occipital lobes smooth; scape, when laid back, not reaching the midlength of head; inner hypostomal tooth indistinct, tooth-like, closely spaced, and directed posteriorly; outer hypostomal tooth lobe-like, high, and moderately wide; median tooth absent; promesonotum short, angular, and moderately low; posterior mesonotum moderately steep; mesonotal process distinct and tubercle-like; mesosoma smooth with very indistinct, and thin rugulae; gaster indistinctly shagreened; body yellow to orange. Minor workers. Occiput not elongated; nuchal collar absent; head sculpture smooth; scape, when laid back, exceeding the posterior head margin by one-fifth of its length; promesonotum moderately low, moderately short, and arched; promesonotal groove present; metanotal groove distinct; propodeal spines indistinct; mesosoma smooth; body yellow.

Description. Major workers. Measurements (n=6): HL: 1.87–2.38 (2.15); HW: 1.88–2.35 (2.07); SL: 0.94– 0.99 (0.96); EL: 0.22–0.26 (0.23); WL: 1.45–1.67 (1.55); PSL: 0.2–0.3 (0.24); MTL: 1.07–1.21 (1.14); PNW: 0.69–0.8 (0.74); PTW: 0.18–0.28 (0.23); PPW: 0.55–0.73 (0.63); CI: 99.7–107.9 (104.0); SI: 39.9–52.4 (46.8); PSLI: 9.7–13.0 (11.2); PPI: 32.9–41.1 (37.4); PNI: 34.2–36.6 (35.7); MTI: 51.4–61.6 (55.3).

Head. In full-face view sub-rectangular, slightly widening posteriorly, with lateral sides slightly convex ( Fig. 17B ). In lateral view sub-oval, not depressed posteriorly; ventral and dorsal margins convex; inner hypostomal tooth visible. Side of head with dense, long, subdecumbent to suberect pilosity; head dorsum with relatively dense, long, suberect to erect pilosity. Antennal scrobes very indistinct; with sparse and very thin rugocostulae; interspaces between rugocostulae smooth. Frons with sparse and thin costulae; interspaces between costulae smooth. Occipital lobes smooth. Gena with moderately dense and thin costulae; interspaces between costulae smooth. Sides posterolateral from eyes smooth; anterior parts indistinctly shagreened. Center of clypeus shiny and smooth, lateral sides with distinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina present; lateral longitudinal carinae present. Scape, when laid back, not reaching the midlength of head; pilosity subdecumbent to erect ( Fig. 17B, D ). Inner hypostomal tooth indistinct, tooth-like, closely spaced, and directed posteriorly; outer hypostomal tooth lobe-like, high, and moderately wide; median tooth absent ( Fig. 27I ). Mesosoma. In lateral view, promesonotum short, angular, and moderately low; posterior mesonotum moderately steep; mesonotal process distinct and tubercle-like; promesonotal groove absent; metanotal groove absent; propodeal spines moderately long, with wide base and acute top; humeral tubercle weakly produced ( Fig. 17D ). Surface mostly smooth, with very indistinct, and thin rugulae. Pilosity moderately dense, long, and erect ( Fig. 17D, F ). Gaster. Shiny and indistinctly shagreened; pilosity moderately dense, long, and erect ( Fig. 17D, F ). Color. Yellow to orange, gaster and mandibles darker ( Fig. 17D, F ).

Description. Minor workers. Measurements (n=7): HL: 0.68–0.77 (0.73); HW: 0.6–0.66 (0.63); SL: 0.85–0.96 (0.9); EL: 0.12–0.14 (0.13); WL: 0.86–1.04 (0.96); PSL: 0.09–0.11 (0.1); MTL: 0.68–0.89 (0.78); PNW: 0.37–0.42 (0.4); PTW: 0.1–0.11 (0.1); PPW: 0.17–0.2 (0.18); CI: 113.3–126.3 (117.0); SI: 132.1–153.6 (143.4); PSLI: 12.9– 15.3 (13.9); PPI: 53.3–63.3 (58.1); PNI: 61.3–65.1 (63.3); MTI: 110.5–144.6 (124.6).

Head. In full-face view oval, posterior region not elongated; nuchal collar absent ( Fig. 17A ). Pilosity relatively sparse, moderately long, subdecumbent to erect. Sculpture smooth; anterolateral frons with weakly developed puncta. 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, subdecumbent to erect ( Fig. 17A, C ). Mesosoma. In lateral view, promesonotum moderately low, moderately short, and arched; promesonotal groove present; metanotal groove distinct; propodeal spines weakly developed and triangular ( Fig. 17C ). Sculpture smooth. Pilosity very sparse, long, and erect ( Fig. 17C, E ). Gaster. With sparse and erect pilosity ( Fig. 17C, E ).

Color. Yellow ( Fig. 17C, E ).

Biology. The species was collected between 475–1200 m elevation, in rainforest and montane rainforest. Nests were located in rotten logs, dead branches above the ground, and root mats. Workers were collected from sifted litter and on low vegetation.

Comments. Pheidole madecassa is most similar to sympatric P. maro . Major workers of P. madecassa can be separated by smooth interspaces between rugocostulae on antennal scrobes, mostly smooth mesosoma with very indistinct and thin rugulae, small inner hypostomal tooth, and yellow to orange body. Majors of P. maro have indistinctly punctate interspaces between rugocostulae on antennal scrobes, sculptured mesosoma, large inner hypostomal tooth, and reddish-brown body. Minor workers of P. madecassa can be distinguished by smooth mesosoma and mostly smooth frons with weakly punctuated anterolateral areas. In contrast, minors of P. maro have indistinctly sculptured frons and mesosoma.

Figures

FIGURE 17. Pheidole madecassa, full-face view (A), profile (C), and dorsal view (E) of minor worker (CASENT0162735) and full-face view (B), profile (D), and dorsal view (F) of major worker (CASENT0923255).

FIGURE 27. Major worker, hypostomal tooth. Pheidole antsahabe (A). Pheidole atsirakambiaty (B). Pheidole bessonii (C). Pheidole clara (D). Pheidole decollata (E). Pheidole flammea (F). Pheidole flavodepressa (G). Pheidole grallatrix (H). Pheidole madecassa (I). Pheidole mantadioflava (J). Pheidole maro (K). Pheidole oswaldi (L). Pheidole ovalinoda (M). Pheidole similis (N). Pheidole tenebrovulgaris (O). Pheidole uranus (P). Pheidole voreios (Q). Pheidole zirafy (R).