Pheidole alfaroi Emery 1896

Formicidae, Hymenoptera, Insecta, Arthropoda, Animalia

worker face view

worker lateral view

major face view

major lateral view


Minor worker: head length 0.74mm, head width 0.59mm, scape length 0.84mm, Webers length 0.90mm (n=1). Head evenly rounded behind, with no vertex collar; mesonotal suture moderately impressed, metanotal groove well-impressed; propodeal spines nearly absent, junction of propodeal dorsum and declivity marked by transverse carina that is slightly produced into tubercles laterally, where spines would be in other species; face, mesosoma, and gaster shiny; thin, sharp, transverse, arcing rugae on posterior face and dorsal mesosoma; gastral dorsum smooth and shiny; dorsal pilosity moderately abundant, of moderate length, flexuous; color yellow; essentially a pale version of innupta.

Major worker: head length 1.42mm, head width 1.30mm, scape length 0.99mm (n=1).


Costa Rica (uplands of Cordillera Central).

Selected Records

The type locality is La Palma, 1500m (within 5km of following site).

Braulio Carrillo National Park (Bajo la Hondura): wet forest; on stalked nectaries on petioles of Impatiens along trail.

Braulio Carrillo National Park: wet forest; common in Winkler samples from 1000-1600m.


Wilson (2003) provisionally synonymized innupta Menozzi under alfaroi. So far, a pattern has held that leads us to treat them as two distinct species. alfaroi is dirty yellow and nests in dead wood on the ground. innupta is always black and nests under epiphytes, usually in the canopy. innupta and alfaroi are sympatric in the Vara Blanca area of Braulio Carrillo National Park.

diana Forel, with which alfaroi may be confused, is yellow, but lacks transverse striae on the vertex.

Literature Cited

Wilson, E. O. 2003. Pheidole in the New World: A Dominant, Hyperdiverse Ant Genus. Harvard University Press, Cambridge, Mass

Page authors:

John T. Longino, The Evergreen State College, Olympia WA 98505 USA.

Stefan Cover, Museum of Comparative Zoology, Harvard University, Cambridge MA 02138 USA.

Date of this version: 2 September 2003.

Previous versions of this page: 26 November 1997
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