The ant genus Pheidole Westwood, 1839 (Hymenoptera: Formicidae) in Madagascar-taxonomic revision of the bessonii species-group Author Salata, Sebastian Author Fisher, Brian L. 0000-0002-4653-3270 bfisher@calacademy.org text Zootaxa 2020 2020-08-31 4843 1 1 64 journal article 8556 10.11646/zootaxa.4843.1.1 a2aef684-44f1-429d-9dd5-dd394539fa36 1175-5326 4405729 57044928-1950-4525-850E-E381A52599A1 Pheidole antsahabe sp. nov. Figs 9 A–F, 27A, 28A HOLOTYPE : 1s., Madagascar , Antsiranana , Forêt d’ Antsahabe , 11.4 km 275° W Daraina , -13.21167 49.55667 , 550 m , 16-Nov-2004 , tropical dry forest, ex rotten log, B. L. Fisher et al . leg. BLF10469, CASENT0107506 ( CASC ). PARATYPES : 1w. , the same data as holotype, CASENT0923247 ( CASC ) . Other material. Madagascar . Antsiranana : 4w. , Ampasindava , Forêt d’Ambilanivy , 3.9 km 181° S Ambaliha , -13.79861 , 48.16167 , 600 m , B. L. Fisher et al . leg. ( CASC ) ; 1s., Binara Forest , -13.26206 , 49.60672 , 559 m , B. L. Fisher et al . leg. ( CASC ) ; 10w. , 7s., Forêt d’ Andavakoera , 21.4 km 75° ENE Ambilobe ; 4.6 km 356° N Betsiaka , -13.11833, 49.23, 425 m , B. L. Fisher et al . leg. ( CASC ) ; 4w. , Forêt d’ Antsahabe , 11.4 km 275° W Daraina , - 13.21167 , 49.55667 , 550 m , B. L. Fisher et al . leg. ( CASC ) ; 2w. , Forêt de Binara , 7.5 km 230° SW Daraina , -13.255 , 49.61667 , 375 m , B. L. Fisher et al . leg. ( CASC ) ; 1w. , 1s., Galoko chain, Mont Galoko , -13.58745 , 48.71419 , 380 m , B. L. Fisher et al . leg. ( CASC ) ; 1w. , Masoala National Park , -15.3014 , 50.22776 , 280 m , B. L. Fisher et al . leg. ( CASC ) ; 2w. , Montagne des Français , 7.2 km 142° SE Antsiranana (= Diego Suarez ), -12.32278 , 49.33817 , 180 m , B. L. Fisher et al . leg. ( CASC ) . Toamasina : 1w. , Corridor Forestier Analamay-Mantadia , Ambatoharanana , - 18.80219 , 48.40585 , 995 m , B. L. Fisher et al . leg. ( CASC ) . Geographic range. Madagascar , northern part of Antsiranana . Diagnosis. Major workers. Head in full-face view sub-rectangular, not widening posteriorly, lateral margins relatively straight; side of head with moderately dense, moderately long, subdecumbent to suberect pilosity; medial frons with dense and thick costulae; frons laterally rugose-punctate; occipital lobe obliquely rugulose; interspaces between rugulae indistinctly punctate to smooth; scape, when laid back, exceeding midlength of head by two-fifths of its length; inner hypostomal tooth indistinct, small, and bulge-like with tip directed posteriorly; outer hypostomal tooth lobe-like, high, and wide with tip directed posteriorly; median tooth absent; promesonotum short, angular, and moderately low; posterior mesonotum moderately steep; mesonotal process distinct and tubercle-like; mesosoma with sparse microreticulae; promesonotum with transverse rugulae; katepisternum and side of propodeum rugose; gaster shagreened; body brown. Minor workers. Occiput forming short and moderately narrow neck; nuchal collar distinct; head mostly smooth; frons with sparse puncta; scape, when laid back, exceeding posterior head margin by three-fifths of its length; promesonotum in lateral view low and moderately long, arched; promesonotal groove present; metanotal groove distinct; propodeal spines with narrow base; promesonotum weakly microreticulate; katepisternum and propodeum punctate; body orange. Description. Major workers. Measurements (n=8): HL: 1.59–1.78 (1.7); HW: 1.49–1.61 (1.55); SL: 1.19– 1.25 (1.21); EL: 0.21–0.28 (0.24); WL: 1.65–1.71 (1.68); PSL: 0.27–0.33 (0.3); MTL: 1.32–1.43 (1.38); PNW: 0.61–0.66 (0.64); PTW: 0.18–0.22 (0.21); PPW: 0.56–0.62 (0.59); CI: 106.9–110.8 (109.4); SI: 75.1–80.8 (78.2); PSLI: 15.9–19.3 (17.5); PPI: 30.0–37.5 (34.8); PNI: 38.7–42.4 (41.0); MTI: 85.9–91.5 (88.7). Head. In full-face view sub-rectangular, not widening posteriorly, side relatively straight ( Fig. 9B ). In lateral view sub-oval, not depressed posteriorly; ventral and dorsal margins convex; inner hypostomal tooth not visible. Side of head with moderately dense, moderately long, subdecumbent to suberect pilosity; head dorsum with relatively dense, long, decumbent to erect pilosity. Medial frons with dense and thick costulae; interspaces between costulae smooth or indistinctly punctate. Frons laterally rugulate; interspaces between rugae punctate; rugae and costulae on posterior frons arch posterolaterally. Occipital lobes with thin rugulae that arch posterolaterally; interspaces between rugulae indistinctly punctate to smooth. Gena with dense and thick costulae; interspaces between costulae indistinctly punctate. Sides posterolateral from eyes with network of dense but very thin rugoreticulae. Center of clypeus shiny and with weakly developed puncta, lateral sides with distinct rugulae; median notch present, moderately wide and shallow; median longitudinal carina present; lateral longitudinal carinae present. Scape, when laid back, exceeding the midlength of head by two-fifths of its length; pilosity subdecumbent to erect ( Fig. 9B, D ). Inner hypostomal tooth indistinct, small and bulge-like, with top directed posteriorly; outer hypostomal tooth lobe-like, high, and wide, with top directed posteriorly; median tooth absent ( Fig. 27A ). 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 present; propodeal spines moderately long with moderately wide base and acute top; humeral tubercle weakly produced ( Fig. 9D ). Surface shiny and with sparse microreticulae; promesonotum with additional transverse and thin rugae; katepisternum and lateral sides of propodeum with additional rugae. Pilosity moderately dense, moderately long, and erect ( Fig. 9D, F ). Gaster. Shiny and shagreened; pilosity moderately sparse, long, and erect ( Fig. 9D, F ). Color. Brown, legs and antennae yellowish-brown ( Fig. 9D, F ). Description. Minor workers. Measurements (n=10): HL: 0.72–0.89 (0.82); HW: 0.46–0.59 (0.52); SL: 0.99– 1.27 (1.15); EL: 0.14–0.18 (0.16); WL: 0.95–1.21 (1.1); PSL: 0.11–0.16 (0.13); MTL: 0.82–1.13 (1.03); PNW: 0.33–0.41 (0.38); PTW: 0.08–0.12 (0.09); PPW: 0.13–0.18 (0.15); CI: 150.8–161.4 (155.8); SI: 206.7–227.3 (220.2); PSLI: 14.8–17.4 (16.2); PPI: 51.2–71.2 (62.9); PNI: 67.1–79.3 (73.6); MTI: 180.3–206.2 (196.6). Head. In full-face view oval, posterior region elongated forming short and moderately narrow neck; nuchal collar distinct ( Fig. 9A ). Pilosity relatively sparse, long, subdecumbent to erect. Sculpture shiny and mostly smooth; frons with sparse puncta. Clypeus without median longitudinal carina; two lateral longitudinal carinae absent. Scape, when laid back, exceeding posterior head margin by three-fifths its length; pilosity dense, subdecumbent to erect ( Fig. 9A, C ). Mesosoma. In lateral view, promesonotum low, moderately long, and arched; promesonotal groove present; metanotal groove distinct; propodeal spines moderate, triangular and with narrow base ( Fig. 9C ). Promesonotum with weak microreticulae; katepisternum and propodeum punctate. Pilosity very sparse, long, and erect ( Fig. 9C, E ). Gaster. With sparse and erect pilosity ( Fig. 9C, E ). Color. Orange, legs and sometimes head brighter ( Fig. 9C, E ). FIGURE 9. Pheidole antsahabe , full-face view (A), profile (C), and dorsal view (E) of paratype minor worker (CASENT0923247) and full-face view (B), profile (D), and dorsal view (F) of holotype major worker (CASENT0107506). Biology. The species was collected between 180–600 m in elevation, in rainforest and tropical dry forest. Nests were located in rotten logs, in soil, and in rotten sticks on the ground. Workers were collected from sifted litter. Comments. Pheidole antsahabe is most similar to the sympatric P. voreios . Major workers of P. antsahabe differ in the smooth to indistinctly punctate interspaces between costulae on the medial frons, and the presence of sparse microreticulae on the promesonotal dorsum. In contrast, P. voreios majors have distinctly punctate interspaces between costulae on the medial frons and mostly to entirely smooth promesonotum. Minors can be separated from P. voreios by the orange body coloration, longer and thinner neck, and sparser sculpture on the promesonotum. Minors of P. voreios have brown body, shorter and thicker neck, and distinctly stronger sculpture on the promesonotum. Additionally, minor workers of P. antsahabe can be confused with P. mantadioflava and P. clara but differ from them in having a longer, narrower neck and a promesonotum that is never entirely smooth nor entirely punctate. Etymology. From the type locality.