Pheidole striaticeps Mayr 1870

Suggested synonyms:
= Pheidole chloe Forel 1908

Formicidae, Hymenoptera, Insecta, Arthropoda, Animalia

worker face view

worker lateral view

major face view

major lateral view


Minor worker: head length 0.54mm, head width 0.51mm, scape length 0.45mm, Webers length 0.61mm (n=1). Head somewhat flattened behind; mesonotal suture absent; propodeal spines short; face and mesosoma foveolate, puncta overlain with very faint rugae; first gastral tergum smooth and shining; setae on promesonotal dorsum very abundant, flexuous; humeral setae longer than surrounding setae and erect; surrounding setae short, subdecumbent; color orange.

Major worker: head length 0.88mm, head width 0.87mm, scape length 0.48mm (n=1). Face with weak antennal scrobes in the form of shallow depressions beneath apices of scapes; face rugose foveolate throughout, rugae longitudinal, subparallel; antennal scrobe also rugose foveolate, not differentially sculptured from surrounding face; hypostomal margin gently curved; median tooth absent; lateral teeth absent (Figure), or in the form of small denticles about one half distance from midline to recessed teeth flanking mandible bases; dorsal pilosity abundant; head with abundant, short, subdecumbent pilosity on sides of head in face view.


Costa Rica, Mexico. Costa Rica: Atlantic slope to 500m and southern Pacific lowlands.

Natural History

Occurs in mature wet forest habitats; nests under loose bark of rotten wood; forages diurnally.

Selected Records

Braulio Carrillo National Park at 500m: diurnal forager.

Rara Avis: mature wet forest; under bark on rotten stump.

La Selva: mature wet forest; under loose bark of large, dead, leaning Cecropia trunk.

La Selva: mature wet forest; nest under loose bark on rotten log.

Corcovado (Sirena): diurnal forager.


The type of striaticeps is from Mexico. Our identification of this species as striaticeps rests on a MCZ collection from Monteverde, which E. O. Wilson compared with the type. We also compared Costa Rican material of this species with a MCZ syntype of chloe Forel 1908. The type locality of chloe is Costa Rica (La Caja, near San Jose), and we determine it to be conspecific with the Costa Rican material we identify as striaticeps. Thus, if the determination by Wilson is correct, chloe is a junior synonym of striaticeps. However, if striaticeps is later found to be a distinct Mexican species, chloe is a firm name for this species.

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: 8 December 1997
Go back to top

Go to Ants of Costa Rica Homepage