Pheidole fiorii Emery

Wilson, E. O., 2003, Pheidole in the New World. A dominant, hyperdiverse ant genus., Cambridge, MA: Harvard University Press, pp. -1--1: 291

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Pheidole fiorii Emery


Pheidole fiorii Emery  HNS 

Pheidole fiorii Emery  HNS  1890c: 51.

Types Mus. Civ. Stor. Nat. Genova; Mus. Comp. Zool. Harvard.

Etymology Named after Andrea Fiori.

diagnosis A medium-sized member of the fallax  HNS  group with extremely long propodeal spines and scapes in both castes. Major: occiput, lateral sections of the head, and posterior strip of pronotum rugoreticulate.

Minor: dorsal surface of head and almost all of mesosoma foveolate to some degree and opaque to subopaque, although the degree of foveolation is variable and parts of the head and promesonotum are often nearly smooth and shiny.

Similar to ajax  HNS  , hector  HNS  , jaculifera  HNS  , and lourothi  HNS  , differing in many details of body form, sculpturing, and pilosity. On variation, John T. Longino (1997) writes: "This species (or species complex) shows a common pattern of being darker at higher elevations ... It also exhibits spatial variation in the pilosity of the major worker head. Collections from sea level to about 600 m on the Atlantic slope are yellow, and the major worker has the sides of head with abundant erect setae. Collections from higher elevations in Braulio Carrillo National Park are dark brown, and the major worker continues to have the sides of head with abundant erect setae. Collections from the Penas Blancas Valley are dark brown, and the major worker has the sides of head with sparse, appressed setae." Measurements (mm) Major (Lago Hula, Costa Rica): HW 1.48, HL 1.52, SL 1.24, EL 0.24, PW 0.68. Minor: HW 0.64, HL 0.92, SL 1.40, EL 0.18, PW 0.48.

Color Yellow to dark brown, with increasing elevation (see under Diagnosis above).

Range Atlantic slope and montane Costa Rica to 950 m.

biology Longino (1997) observes, as I have, that fiorii  HNS  "inhabits mature wet forest understory. It makes hemispherical carton nests under individual leaves of palms, aroids, and other large-leaved plants. The nests are on the order of 10 cm across, and usually at head height or lower. Colonies appear to be monogynous and with a single nest." Longino notes also that fiorii  HNS  has varied greatly in abundance at La Selva and Penas Blancas from one season or year to the next, for unknown reasons. At Penas Blancas he observed a nest being raided by a colony of the army-ant-like ponerine genus Simopelta  HNS  .

Figure Upper: major. Lower: minor. COSTA RICA: Lago Hula, Heredia (E. O. Wilson). (The minor was compared with a syntype in the Museum of Comparative Zoology, Harvard University; type locality is Jimenez, Costa Rica; collected by Anastasio Alfaro.) Scale bars = 1 mm.