Pheidole mackayi

Longino, J. T., 2009, Additions to the taxonomy of New World Pheidole (Hymenoptera: Formicidae)., Zootaxa 2181, pp. 1-90 : 52-54

Pheidole mackayi

Figure 14

Pheidole mackayi Wilson 2003: 448 , figs (part, minor worker is misidentified P janzeni ). Holotype major worker: Mexico, Chiapas, 24km SW Cintalpa [Cintalapa], 710m, 2 Jun 1988, slashed and burned area, surface bait trap Vienna sausage (W. M. MacKay #10717I) [ MCZ] (examined).

Geographic Range

Mexico (Chiapas).

Description of minor worker (previously undescribed)

Measurements (n=1): HL 0.60, HW 0.51, SL 0.65, HLA 0.21, EL 0.13, ML 0.73, PSL 0.05, PMG 0.02, SPL 0.02, PTW 0.11, PPW 0.16, CI 85, SI 126, PSLI 9, PMGI 4, SPLI 4, PPI 146.

Mandible roughened, dull at base, grading to smooth and shiny near masticatory margin; clypeus strongly convex, largely smooth and shining with 2-4 longitudinal rugulae; face largely smooth and shiny, with faint foveolate sculpture between frontal carina and compound eye, extending posterior to compound eye on side of head, small irregular patches of faint fovelate sculpture elsewhere; margin of vertex flattened posteriorly; occipital carina narrow, barely visible in full face view; scape foveolate, with abundant decumbent setae and sparse suberect setae that are subequal in length to maximum width of scape; promesonotal groove present; propodeal spines present; pronotum foveolate with dorsal shiny patch; katepisternum and propodeum foveolate; about 12 short, curved, somewhat stiffened setae on mesosomal dorsum; dorsal (outer) margin of hind tibia with short decumbent setae and sparse suberect setae that are subequal in length to maximum width of tibia; dorsal surface of postpetiole faintly foveolate; first gastral tergum with fine short striations near postpetiolar insertion, smooth and shining elsewhere; gastral dorsum with moderately abundant, somewhat stiff setae; color red brown.

Description of major worker

Measurements (holotype): HL 0.86, HW 0.84, SL 0.52, EL 0.12, IHT 0.28, OHT 0.35, CI 98, SI 62, HTI 79.

Mandible shiny, with coarse piligerous puncta, coarse striae at base; clypeus smooth and flat with distinct anterior notch; frontal carinae somewhat elevated and laminar; face rugose foveolate on sides of head between frontal carina and compound eye, gradually fading behind eye to smooth and shiny vertex lobes (extent of shiny area variable), medial area an irregular mixture of smooth and shiny patches, longitudinal rugulae near frontal carinae, and patches of faint foveolate sculpture; posterior margin of vertex with sparse stiff erect setae, side of head in full face view with short appressed setae only, no projecting erect setae; scape foveolate, terete at base, with appressed pubescence and sparse erect setae subequal in length to maximum width of scape; hypostomal margin gently curved; median tooth small to absent; inner hypostomal teeth minute denticles (may be drawn out into thin, needle-like spines) closer to outer hypostomal teeth than to midline; promesonotal groove present; propodeal spines present; mesosoma largely foveolate with variable extent of shiny patch dorsally; dorsal (outer) margin of hind tibia with appressed pubescence and sparse erect setae subequal in length to maximum width of tibia; 12-14 stiff erect setae on mesosomal dorsum; postpetiole in dorsal view globular, wider than long, faintly foveolate; first gastral tergum with small area of fine short striations near postpetiolar insertion, smooth and shining elsewhere; gastral dorsum with abundant, somewhat stiff setae; color red brown.

Biology

This species occurs in disturbed habitats in seasonally dry climates, from 700-1400m elevation. The few collections, minor and major workers, have been from baits.

Comments

Additional collections of P. mackayi from near the type locality and sympatric collections of the new species P janzeni revealed that the type collection of P. mackayi was a mixed series.

Additional material examined

MEXICO: Chiapas, Sierra Morena, 16°09'15"N, 93°35'23"W, 1150m (J. Longino).