Pheidole idiota

Identification
Pheidole idiota can be easily recognized by the basally broad scape which surpasses the midheight between the eyes and the vertexal margin, not reaching the margin. The only morphologically similar species is Pheidole porcula. Both species can be distinguished by the gaster pilosity, which in P. idiota the setae have no more than 1.5× the eye length, while in P. porcula the setae are more than 1.5× the eye length. Minors of P. idiota are similar to several species included in the diligens group and the complete description is necessary to distinguish them.

Distribution
The current disjunct distribution of P. idiota is probably an artifact from the fact that several records for the species in Mesoamerica and southern South America have been attributed to P. laticornis and P. vafra, respectively.

Distribution based on Regional Taxon Lists
Neotropical Region: Argentina, Brazil, Costa Rica.

Nomenclature

 * . Pheidole idiota Santschi, 1923d: 53 (s.w.q.) ARGENTINA.
 * Subspecies of vafra: Santschi, 1929d: 284.
 * Material of the unavailable name maculifrons referred here by Brown, 1981: 526; Casadei-Ferreira, Economo & Feitosa, 2020: 9.
 * Junior synonym of vafra: Wilson, 2003: 244.
 * Senior synonym of laticornis: Casadei-Ferreira, Economo & Feitosa, 2020: 9.
 * Status as species: Casadei-Ferreira, Economo & Feitosa, 2020: 9.
 * laticornis. Pheidole laticornis Wilson, 2003: 203, figs. (s.w.) COSTA RICA.
 * Junior synonym of vafra: Longino, 2019: 63.
 * Junior synonym of idiota: Casadei-Ferreira, Economo & Feitosa, 2020: 9.

Taxonomic Notes
This species has been a junior synonym of Pheidole vafra since Wilson (2003). Wilson (2003) described Pheidole laticornis and considered the scape basally broad of majors as the main diagnostic character of the species. However, P. idiota presents the same character and lacks any significant morphological difference when compared to P. laticornis. In a recent publication, Longino (2019) synonymized P. laticornis under Pheidole vafra, considering the similarity between the images of both types. After examining a large number of specimens, including the sympatric populations of Paraná state (see Franco & Feitosa (2018) for the records), as well the type series and its synonyms, we consider that P. vafra can be securely distinguished from P. idiota by the consistency of the diagnosis above. We revive P. idiota to species with P. laticornis as its junior synonym.