Pheidole orbica

P. orbica may be a native species on St. Vincent and is likely local in distribution; Stefan Cover and I did not encounter it during a week’s collecting on the neighboring island of Grenada. H. H. Smith (in Forel 1893j) found it rare on St. Vincent, in well-developed forest, nesting in pieces of rotting wood on the ground, under stones in the soil, or, in one case, beneath sod on a stone. Each colony contained several hundred individuals. (Wilson 2003)

Identification
See the description in the nomenclature section.

Distribution
From Wilson (2003): Known from St. Vincent, West Indies, and from Arroyo, Puerto Rico, col. J. A. Torres.

This taxon was described from Antilles.

Description
DIAGNOSIS A member of the “flavens complex” within the larger flavens group, consisting of Pheidole asperithorax, Pheidole breviscapa (=Pheidole perpusilla), Pheidole exigua, Pheidole flavens, Pheidole nuculiceps, Pheidole orbica and Pheidole sculptior, as well as the less similar Pheidole nitidicollis and species placed close to it (see under nitidicollis), differing by the following combination of traits.

Major: occiput and entire body behind the head smooth and shiny; shallow antennal scrobes present, their surfaces partly carinulate and foveate and subopaque; a small patch of rugoreticulum present just laterad to the circular carinulae of the antennal fossae; longitudinal carinulae originating on the frontal lobes reach almost to the occiput, and those just mesad to the eye reach to halfway between the eye and occipital corner; promesonotum in side view forms a near-perfect semicircle; apex of petiolar node in side view acute.

Minor: except for sparse circular carinulae around the antennal fossae, head and body entirely smooth and shiny.

MEASUREMENTS (mm) Lectotype major: HW 0.82, HL 0.88, SL 0.42, EL 0.10, PW 0.38. Paralectotype minor: HW 0.40, HL 0.40, SL 0.36, EL 0.06, PW 0.24.

COLOR Major: body variably brownish yellow to light reddish brown.

Minor: body yellowish brown, appendages clear yellow.



'''Figure. Upper: lectotype, major. Lower: paralectotype, minor. Scale bars = 1 mm.'''

Type Material
- as reported in Wilson (2003)

Type Locality Information
ST. VINCENT, WEST INDIES, col. H. H. Smith. (Wilson 2003)

Etymology
L orbica, circular, possibly referring to the semicircular profile of the promesonotum. (Wilson 2003)

Additional References
Forel, A. 1893. Formicides de l’Antille St. Vincent, récoltés par Mons. H. H. Smith. Trans. Entomol. Soc. Lond. 1893: 333–418.

Text and images from this publication used by permission of the author.