Pheidole hansoni new species

(Plate 28)

Pheidole JTL-140: morphospecies code previously used on AntWeb.

HOLOTYPE: 1 major worker, Costa Rica, Guanacaste: Cerro Cacao, 10.92682 -85.46823 ± 2 km, 1100 m, 13- Feb-1995, moist forest, nest under stone (J. Longino, JTL3659) [MUCR, unique specimen identifier CASENT0636565] . PARATYPES: major, minor workers: same data as holotype [JTLC, MCZC, MUCR] .

Geographic range. Costa Rica.

Diagnosis. Minor: face foveolate, overlain with irregular rugulae, rugulae becoming more longitudinal medially; promesonotal profile somewhat box-like, promesonotal groove very shallowly impressed, posterior mesonotum dropping steeply to propodeum; entire mesosoma foveolate, overlain with a lattice of rugulae on dorsal pronotum; propodeal spines upturned, about half as long as posterior face of propodeum; gaster smooth and shining; abundant flexuous erect setae on mesosomal and gastral dorsa, lacking on tibiae; color dark red brown. Major: inner hypostomal teeth large, closely spaced; scape base terete; face with longitudinal rugulae and faint foveolation between eye and frontal carinae, very feeble longitudinal carinulae on frontal space between frontal carinae (variably present), rest of face smooth and shining; propodeal spines about a third to half length of posterior face of propodeum; gastral dorsum smooth and shining; abundant, erect, flexuous setae on face, sides of head, mesosomal dorsum, and gastral dorsum; tibiae lacking erect setae or with one or two inconspicuous setae; in one series, setae on head subdecumbent, giving somewhat wooley appearance; color dark red brown.

Measurements, minor worker: HW 0.53, HL 0.56, SL 0.47, EL 0.10, WL 0.64, PSL 0.09, PTW 0.10, PPW 0.15, CI 94, SI 90, PSLI 17, PPI 157 (n=5).

Measurements, major worker: HW 1.02, HL 1.09, SL 0.51, EL 0.13, WL 0.82, PSL 0.10, PTW 0.18, PPW 0.34, CI 94, SI 50, PSLI 10, PPI 181 (n=3).

Biology. This species occurs in montane moist to wet forest. One collection was from a nest under a stone in mature forest. Another collection was major and minor workers at a ground bait.

Comments. The few collections of this species come from widely separated populations in Costa Rica, and the major workers exhibit a relatively broad range of measurements (one each from three populations: HW 0.99-1.10, CI 92-97). Pheidole carinitida is superficially similar but has enlarged frontal carinae and a more impressed promesonotal impression, in both minors and majors.

Etymology: In honor of Paul Hanson, who has been a tireless facilitator and promoter of entomological research in Costa Rica.