Pheidole idiota

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Pheidole idiota
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Pheidole
Species group: diligens
Species: P. idiota
Binomial name
Pheidole idiota
Santschi, 1923


Casadei-Ferreira et al. (2020): 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.


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 (type locality), Brazil, Costa Rica (type locality).

Distribution based on AntMaps


Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.




The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

  • idiota. 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.

Type Material

Taxonomic Notes

Casadei-Ferreira et al. (2020): 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.