Pheidole aberrans

Bruch (1916) describes typical nests of aberrans in San Luis Province, Argentina, as excavated in open ground, comprising a single conspicuous hole, surrounded by a ring of excavated soil, and leading to a succession of flat-bottomed chambers about 5 cm across and up to 2 cm high, which are connected by vertical galleries. Trager (unpublished specimen data) has collected Pheidole aberrans in cactus scrub, overgrazed pasture, a residential backyard, and on roadsides. (Wilson 2003)

Identification
See the description in the nomenclature section.

Distribution
Recorded by Kempf (1972b) from Buenos Aires and San Luis provinces of Argentina north to Goiás and Pernambuco states in central Brazil. It has also been collected near Cuzco in Peru, and near Cochabamba, Bolivia (MCZ). (Wilson 2003)

Distribution based on Regional Taxon Lists
Neotropical Region: Argentina, Bolivia, Brazil, Paraguay, Peru.

Nomenclature

 *  aberrans. Pheidole aberrans Mayr, 1868b: 172 (s.w.) ARGENTINA. Emery, 1906c: 142 (q.); Forel, 1913l: 232 (m.). Combination in P. (Elasmopheidole): Forel, 1913k: 43. Senior synonym of diversiceps, fartilia, mutica: Wilson, 2003: 131. See also: Bruch, 1914: 219; Bruch, 1916: 312.
 * mutica. Pheidole aberrans var. mutica Emery, 1906c: 142, fig. 19 (s.) ARGENTINA. Combination in P. (Elasmopheidole): Emery, 1922e: 111. Junior synonym of aberrans: Wilson, 2003: 131.
 * fartilia. Pheidole (Elasmopheidole) aberrans var. fartilia Forel, 1913l: 233 (s.) ARGENTINA. Junior synonym of aberrans: Wilson, 2003: 131.
 * diversiceps. Pheidole (Elasmopheidole) aberrans var. diversiceps Santschi, 1916e: 374 (s.w.q.) ARGENTINA. Junior synonym of aberrans: Wilson, 2003: 131.

Description
From Wilson (2003): A member of the aberrans group, closest to Pheidole cavifrons, Pheidole longior, and Pheidole obnixa, distinguished as follows.

Major: frontal lobes seen from above bilaterally symmetrical, coming to a point an Eye Length from the anterior clypeal border; all of dorsal surface of head carinulate, except for a broad space posterior to the demarcating occipital carina; all pre-carina carinulae turnaway (laterad) as they approach the carina; pronotum in dorsal-oblique view very high above smaller but well-developed mesonotal convexity, and semicircular in outline; hypostoma 2-toothed; propodeal spines well developed.

Minor: promesonotal dorsum covered with semicircular carinulae; posterior dorsal surface of head smooth or partially carinulate; propodeal spines well developed.

MEASUREMENTS (mm) Major (Tucumán): HW 1.40, HL 1.64, SL 0.56, EL 0.14, PW 0.86. Minor (Tucumán): HW 0.68, HL 0.70, SL 0.46, EL 0.10, PW 0.44.

COLOR Major: light reddish brown except for clypeus and edges of frontal lobes, which are plain medium brown.



'''Figure. Upper: major. Lower: minor. ARGENTINA: Tucumán, col. N. Kusnezov. Scale bars = 1 mm.'''

Type Material
- as reported in Wilson (2003)

Type Locality Information
Buenos Aires, Argentina. col. P. de Strobel.

Etymology
L aberrans, wandering, astray, with possible reference to unusual major head. (Wilson 2003)

Additional References
Bruch, C. 1916. Contribución al estudio de las hormigas de la provincia de San Luis. Rev. Mus. La Plata 23: 291–357.

Kempf, W. W. 1972d. A study of some Neotropical ants of genus Pheidole Westwood. I. (Hymenoptera: Formicidae). Stud. Entomol. 15: 449–464.

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