Pheidole heterothrix

One series, collected by W. L. Brown at Horco Molle, Tucumán, was found at 900–1150 m in myrtaceous forest. (Wilson 2003)

Identification
See the description in the nomenclature section.

Distribution
In addition to the types, from Villaguay, Entre Rios, Argentina, I have seen series from the Argentine provinces of La Pampa, Misiones, and Tucumán. (Wilson 2003)

Distribution based on Regional Taxon Lists
Neotropical Region: Argentina.

Worker
Minor

Nomenclature

 *  heterothrix. Pheidole obtusopilosa st. heterothrix Santschi, 1923d: 59 (s.w.) ARGENTINA. Raised to species and senior synonym of gavrilovi: Wilson, 2003: 436.
 * gavrilovi. Pheidole gavrilovi Kusnezov, 1952b: 80 (s.w.) ARGENTINA. Junior synonym of heterothrix: Wilson, 2003: 436.

Description
From Wilson (2003): DIAGNOSIS Similar to Pheidole obtusopilosa in some traits but distinguished from it and other Pheidole species as follows.

Major: patch of rugoreticulum present between eye and antennal fossa on each side; entire remainder of dorsal surface of head, including occiput, carinulate; very faint antennal scrobe present; promesonotal profile smoothly rounded; mesonotal convexity low but with distinct anterior and posterior declivities; all of pronotum carinulate; humeri rugoreticulate; pilosity dense and short; postpetiole from above conulate.

Minor: humerus subangulate; propodeal spines robust, moderately long, and directed backward; all of body except gaster foveolate.

MEASUREMENTS (mm) Lectotype major (heterothrix, not “gavrilovi”): HW 1.12, HL 1.16, SL 0.54, EL 0.18, PW 0.62.

Paralectotype minor: HW 0.54, HL 0.54, SL 0.44, EL 0.10, PW 0.32.

COLOR Major: all of body light reddish brown except gaster, which is medium reddish brown.

Minor: body dark reddish brown, appendages medium reddish brown.



'''Figure. Upper: major (syntype of synonymous gavrilovi). Lower: minor (syntype of synonymous gavrilovi). Upper outlines of minor mesosoma and occiput are those of heterothrix syntype. ARGENTINA: Loreto, Misiones, Argentina. Compared with lectotype and paralectotype of heterothrix. Scale bars = 1 mm.'''

Type Material
Villaguay, Entre Rios, Argentina. - as reported in Wilson (2003)

Etymology
Gr heterothrix, different hair (from that of obtusopilosa). (Wilson 2003)

References based on Global Ant Biodiversity Informatics

 * Cuezzo, F. 1998. Formicidae. Chapter 42 in Morrone J.J., and S. Coscaron (dirs) Biodiversidad de artropodos argentinos: una perspectiva biotaxonomica Ediciones Sur, La Plata. Pages 452-462.
 * Kempf, W.W. 1972. Catalago abreviado das formigas da regiao Neotropical (Hym. Formicidae) Studia Entomologica 15(1-4).
 * Kusnezov N. 1952. El género Pheidole en la Argentina (Hymenoptera, Formicidae). Acta Zoologica Lilloana 12: 5-88.
 * Kusnezov N. 1978. Hormigas argentinas: clave para su identificación. Miscelánea. Instituto Miguel Lillo 61:1-147 + 28 pl.
 * Vittar, F. 2008. Hormigas (Hymenoptera: Formicidae) de la Mesopotamia Argentina. INSUGEO Miscelania 17(2):447-466