Pheidole hazenae Wilson 2003

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 0.50mm, scape length 0.49mm, Webers length 0.59mm (n=1). Head rounded behind, with median impression; mesonotal suture very weak, barely visible as a slight impression; propodeal spines short, upturned; postpetiole globular, little wider than petiole in dorsal view; face and mesosoma uniformly foveolate with the exception of the katepisternum, which is smooth and shiny; first gastral tergum smooth and shining; dorsal setae abundant, medium length, flexuous; color orange.

Major worker: head length 0.99mm, head width 0.96mm, scape length 0.53mm (n=1). Face longitudinally rugose, interspaces weakly foveolate, becoming smooth and shiny on posteriormost face and vertex lobes; hypostomal margin gently curved; median tooth present; lateral teeth pointed, stout, about one third distance from midline to recessed teeth flanking mandible bases; dorsal pilosity abundant; head with abundant suberect setae projecting from sides of head in face view; postpetiole trapezoidal in dorsal view.


Ecuador, Costa Rica. Costa Rica: Cordillera Volcanica Central, Volcan Barva transect, 1100m.

Natural History

The types of this species are from Rio Palenque Biological Station in Ecuador, a mid-elevation wet forest site on the west slope of the Andes. The Costa Rica collections are from two sites on the Barva Transect, on the Atlantic slope of te Cordillera Volcanica Central. At an 1100m site, workers were collected on the ground in a recent clearing. At a 500m site, workers were obtained in several sifted litter samples from the forest floor.


The determination of the Costa Rican material as hazenae is very tenuous, since hazenae is known from a single major worker and is in a group with many similar species. But direct comparison of a Costa Rican major with the holotype revealed that they were nearly identical. The hazenae holotype has the katepisternum with a rim of foveolate sculpture around a median shiny patch, while on the Costa Rican major the katepisternum is entirely smooth and shining.

Two other species, alacris and subreticulata, also look similar. Pheidole alacris is a Santschi name and subreticulata is an Emery name and there are no types at MCZ. Wilson's illustrations of major workers look like they could match, but it is hard to tell from just illustrations. No minor workers of these are described in the Wilson monograph.

In the Wilson monograph additional material from Colombia is identified as hazenae, but these are not conspecific and look more like a version of ruida.

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 2008.
Previous versions of this page: 7 October 2003.
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