Pheidole similis,

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: 49-51

publication ID

https://doi.org/10.11646/zootaxa.4843.1.1

publication LSID

lsid:zoobank.org:pub:57044928-1950-4525-850E-E381A52599A1

DOI

http://doi.org/10.5281/zenodo.4488403

persistent identifier

http://treatment.plazi.org/id/03938025-FFBE-A924-A7D8-B26AFAE7F9F5

treatment provided by

Plazi

scientific name

Pheidole similis
status

sp. nov.

Pheidole similis  sp. nov.

Figs 22View FIGURE 22 A–F, 27N, 28N

HOLOTYPE: 1s., Madagascar, Antsiranana, Nosy Be, Réserve Naturelle Intégrale de Lokobe , 6.3 km 112° ESE Hellville, -13.41933 48.33117, 30 m, 19-Mar-2001, rainforest, ex rotten log, Fisher et al. leg. BLF03447View Materials, CASENT0427852 ( CASC)GoogleMaps  . PARATYPES: 2w., the same data as holotype, CASENT0427853, CASENT0427854 ( CASC, MHNG)GoogleMaps  .

Other material. Madagascar. Antsiranana: 3w., Nosy Be, Réserve Naturelle Intégrale de Lokobe , 6.3 km 112° ESE Hellville, -13.41933 48.33117, 30 m, Fisher et al. leg. ( CASC)GoogleMaps  ; 7w., 1s., Nosy Be, Réserve Naturelle Intégrale de Lokobe , 6.3 km 112° ESE Hellville, -13.41933 48.33117, 30 m, Fisher et al. leg. ( CASC)GoogleMaps  .

Geographic range. Madagascar, Antsiranana, Nosy Be.

Diagnosis. Major workers. Head in full-face view sub-rectangular, not widening posteriorly, with lateral margins relatively straight; side of head with moderately sparse, short, subdecumbent to suberect pilosity; medial frons with moderately sparse and thick costulae; interspaces between costulae smooth; frons laterally with thick rugocostulae; interspaces between rugocostulae rugulate; occipital lobes with thick rugae; interspaces between rugae smooth; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal tooth distinct, small, bulge-like, with top arching posteroventrally; outer hypostomal tooth lobe-like, high, and wide, with top directed posteriorly; median tooth absent; promesonotum short, angular, and moderately low; posterior mesonotum moderately steep; mesonotal process distinct and tubercle-like; mesosoma microreticulate; promesonotal dorsum with sculpture reduced; gaster shagreened; body orange. Minor workers. Occiput elongated forming short and moderately narrow neck; nuchal collar distinct; head sculpture smooth; scape, when laid back, exceeding the posterior head margin by two-fifths of its length; promesonotum low, long, and arched; promesonotal groove present; metanotal groove distinct; propodeal spines moderate with narrow base; promesonotum smooth; katepisternum and propodeum with sparse puncta; body yellow.

Description. Major workers. Measurements (n=2): HL: 1.55, 1.58; HW: 1.38, 1.47; SL: 1.18, 1.14; EL: 0.21, 0.21; WL: 1.46, 1.44; PSL: 0.3, 0.31; MTL: 1.17, 1.17; PNW: 0.56, 0.58; PTW: 0.21, 0.21; PPW: 0.43, 0.5; CI: 112.2, 107.7; SI: 85.5, 77.7; PSLI: 19.2, 19.3; PPI: 48.1, 41.8; PNI: 40.3, 39.7; MTI: 84.8, 79.9.

Head. In full-face view sub-rectangular, not widening posteriorly, with lateral sides relatively straight ( Fig. 22BView FIGURE 22). In lateral view sub-oval, not depressed posteriorly; ventral and dorsal margins convex; inner hypostomal tooth not visible. Side of head with moderately sparse, short, subdecumbent to suberect pilosity; head dorsum with relatively dense, long, decumbent to erect pilosity. Medial frons with moderately sparse and thick costulae; interspaces between costulae smooth. Frons laterally with thick rugocostulae; interspaces between rugocostulae rugulate. Occipital lobes with thick rugae; interspaces between rugae smooth. Gena with dense and thick costulae; interspaces between costulae smooth. Sides posterolateral from eyes with dense but very thin network of rugoreticulae; sculpture slightly weakening posteriorly. Center of clypeus shiny and smooth, lateral sides with distinct 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 two-fifths of its length; pilosity subdecumbent to erect ( Fig. 22B, DView FIGURE 22). Inner hypostomal tooth distinct, small, bulge-like, with top arching posteroventrally; outer hypostomal tooth lobe-like, high, and wide, with top directed posteriorly; median tooth absent ( Fig. 27NView FIGURE 27). 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 narrow base and acute top; humeral tubercle weakly produced ( Fig. 22DView FIGURE 22). Surface shiny and microreticulate; promesonotal dorsum with sculpture reduced. Pilosity moderately dense, moderately long, and erect ( Fig. 22D, FView FIGURE 22). Petiole. In rear view node dorsoventrally slightly convex ( Fig. 22D, FView FIGURE 22). Gaster. Shiny and shagreened; pilosity moderately sparse, long, and erect ( Fig. 22D, FView FIGURE 22). Color. Orange, legs yellow, gaster darker than mesosoma ( Fig. 22D, FView FIGURE 22).

Description. Minor workers. Measurements (n=10): HL: 0.7–0.89 (0.81); HW: 0.46–0.57 (0.52); SL: 1.01– 1.28 (1.18); EL: 0.13–0.17 (0.14); WL: 0.89–1.24 (1.06); PSL: 0.12–0.17 (0.15); MTL: 0.79–1.2 (0.99); PNW: 0.32–0.44 (0.37); PTW: 0.07–0.12 (0.09); PPW: 0.12–0.21 (0.15); CI: 152.4–161.2 (156.0); SI: 220.8–237.2 (228.0); PSLI: 15.1–20.7 (18.2); PPI: 52.4–70.6 (61.6); PNI: 68.2–77.4 (71.5); MTI: 161.5–211.0 (190.5).

Head. In full-face view oval, posterior region elongated forming short and moderately narrow neck; nuchal collar distinct ( Fig. 22AView FIGURE 22). Pilosity relatively sparse, long, and subdecumbent to erect. Sculpture shiny and mostly smooth; antennal sockets with few indistinct rugulae that are curved posterolaterally; interspaces between rugulae smooth. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, exceeding the posterior head margin by two-fifths of its length; pilosity dense, subdecumbent to erect ( Fig. 22A, CView FIGURE 22). Mesosoma. In lateral view, promesonotum low, long, and arched; promesonotal groove present; metanotal groove distinct; propodeal spines moderate and triangular, with narrow base ( Fig. 22CView FIGURE 22). Promesonotum smooth; katepisternum and propodeum sparsely punctate. Pilosity very sparse, long, and erect ( Fig. 22C, EView FIGURE 22). Gaster. With sparse and erect pilosity ( Fig. 22C, EView FIGURE 22). Color. Yellow, gaster and head darker than mesosoma ( Fig. 22C, EView FIGURE 22).

Biology. The species was collected at 30 m elevation, in rainforest. Nests were located in rotten logs. Workers were collected from sifted litter.

Comments. Among species known from Nosy Be islet, Pheidole similis  is the only member of the bessonii  group with both minor and major workers yellow to orange. It is most similar to two species known from the eastern parts of Antsiranana and the northernmost part of Toamasina: P. clara  and P. mantadioflava  . Its major workers differ from these two taxa in frons laterally with thick rugocostulae, and with rugulate interspaces between rugulae. Majors of P. clara  and P. mantadioflava  have frons laterally entirely punctate or rugulate with punctate interspaces between rugulae. Minor workers can be easily separated based on smooth promesonotum. Pheidole similis  is morphologically most similar to P. ragnax  , described by Fischer & Fisher from Mayotte island. Minors of P. similis  can be separated based on longer and more narrow neck, and presence of sparse but distinct puncta on katepisternum and propodeum. Majors differ in more rugulate lateral frons, sparser setae on sides of head, more distinct and dense mesosomal sculpture, and shagreened gaster.

Etymology. Latin for similar, in reference to the morphological similarity of P. similis  to P. ragnax  .

MHNG

Museum d'Histoire Naturelle

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Hymenoptera

Family

Formicidae

Genus

Pheidole