Pheidole tepicana

In the Santa Cruz Mountains of Arizona, Stefan Cover (unpublished notes) found a colony of tepicana in an open area with opuntia and dwarf acacia surrounded by blue oak, nesting under a stone in the sun; the nest contained a cache of seeds. The species is notably flexible in its choices of nest site. Near Tucson, Arizona, I observed a colony in an open grassy area, spread out beneath multiple stones. In western Texas, Moody and Francke (1982) found numerous colonies, nesting mostly under stones and in open soil; one colony each was also beneath a log, a piece of metal, and a grass clump respectively. And finally, at Cuernavaca, Wheeler (1901b) observed that colonies were common beneath pats of half-dried cow dung. (Wilson 2003)

Identification
See the description in the nomenclature section.

Distribution
Texas, Arizona southward to at least Jalisco, Mexico: often locally abundant. (Wilson 2003)

Distribution based on Regional Taxon Lists
Nearctic Region: United States. Neotropical Region: Mexico.

Castes
Unusual in having three discrete worker castes.

The following images are provided by Harvard Museum of Comparative Zoology and Antweb.org

Worker
Minor

Nomenclature

 * carbonaria. Pheidole carbonaria Pergande, 1896: 881 (s.w.) MEXICO. Junior synonym of tepicana: Emery, 1901b: 119.
 * rugifrons. Pheidole rugifrons Pergande, 1896: 880 (s.) MEXICO. Junior synonym of tepicana: Emery, 1901b: 119.
 *  tepicana. Pheidole tepicana Pergande, 1896: 878 (s.w.) MEXICO. Taber & Cokendolpher, 1988: 95 (k.). Senior synonym of carbonaria, rugifrons: Emery, 1901b: 119; of instabilis, kingi (and its junior synonym townsendi), torpescens: Creighton & Gregg, 1955: 24. See also: Wilson, 2003: 601.
 * kingi. Pheidole kingi André, 1898: 244 (s.w.) MEXICO. Combination in P. (Allopheidole): Forel, 1912f: 237. Senior synonym of townsendi: Emery, 1922e: 105. Junior synonym of tepicana: Creighton & Gregg, 1955: 24.
 * townsendi. Pheidole townsendi André, 1898: 246 (s.w.) MEXICO. Junior synonym of kingi: Emery, 1922e: 105.
 * instabilis. Pheidole kingi subsp. instabilis Emery, 1901b: 120 (s.w.) U.S.A. Wheeler, W.M. 1908e: 433 (q.m.); Wheeler, G.C. & Wheeler, J. 1953b: 74 (l.). Junior synonym of tepicana: Creighton & Gregg, 1955: 24.
 * torpescens. Pheidole kingi subsp. torpescens Wheeler, W.M. 1915b: 404 (s.w.) U.S.A. Junior synonym of tepicana: Creighton & Gregg, 1955: 24.

Description
From Wilson (2003): DIAGNOSIS A member of the “pilifera complex” of the larger pilifera group; for a characterization of the complex, see under Pheidole pilifera.

P. tepicana is distinguished within the complex as follows. Trimorphic, with major, supermajor, and minor castes.

Major: posterior half of dorsum of head except for occiput smooth and shiny; pronotum low and smoothly convex; mesonotal convexity very low; postpetiole from above diamond-shaped. Supermajor: posterior third of head covered by a mixture of rugulae and rugoreticula; rugoreticulum present between eye and antennal fossa.

Minor: propodeal spines reduced to denticles; head almost entirely smooth and shiny.

MEASUREMENTS (mm) Major (Austin, Texas): HW 1.12, HL 1.34, SL 0.62, EL 0.12, PW 0.54. Supermajor (Guadalajara, Mexico): HW 1.62, HL 2.00, SL 0.74, EL 0.14, PW 0.74. Minor (Austin, Texas): HW 0.52, HL 0.56, SL 0.52, EL 0.12, PW 0.32.

COLOR Major: reddish yellow.

Supermajor: light reddish brown.

Minor: brownish yellow.



'''Figure. Upper: major (plus partial frontal head view of a supermajor). Lower: minor. TEXAS: major and minor from Austin (syntypes of the synonymy kingi subsp. instabilis Emery); supermajor from Guadalajara, Jalisco, Mexico. Scale bars = 1 mm.'''

Type Material
and  - as reported in Wilson (2003)

Type Locality Information
Mexico Tepic, Nayarit, collected by Eisen and Vaslit. (Wilson 2003)

Etymology
Name based on type locality. (Wilson 2003)