Longino (1997) observes, as I have, that fiorii “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 has varied greatly in abundance at La Selva and Peñas Blancas from one season or year to the next, for unknown reasons. At Peñas Blancas he observed a nest being raided by a colony of the army-ant-like ponerine genus Simopelta. (Wilson 2003)
See the description in the nomenclature section.
Keys including this Species
Atlantic slope and montane Costa Rica to 950 m. (Wilson 2003)
Distribution based on Regional Taxon Lists
Distribution based on AntMaps
Distribution based on AntWeb specimens
Check data from AntWeb
Nest described in Black (1987).
A colony (nest pictured below) included one dealate queen, 646 workers, 67 soldiers, 6 gynes, larvae and over 400 pupae (workers 414, soldiers 5, gynes 17) (C. Peeters unpublished).
The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.
- fiorii. Pheidole fiorii Emery, 1890b: 51 (s.) COSTA RICA. Forel, 1899c: 70 (q.); Forel, 1908b: 52 (w.m.). [Also described as new by Emery, 1894k: 56.] See also: Wilson, 2003: 291.
Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.
From Wilson (2003): A medium-sized member of the fallax 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.
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 Peñas 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.
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) Scale bars = 1 mm.
Named after Andrea Fiori. (Wilson 2003)
- Black, R.W. 1987. The biology of leaf nesting ants in a tropical wet forest. Biotropica 19: 319-325.
- Emery, C. 1890c. Studii sulle formiche della fauna neotropica. Bull. Soc. Entomol. Ital. 22: 38-80 (page 51, soldier described)
- Emery, C. 1894l. Estudios sobre las hormigas de Costa Rica. An. Mus. Nac. Costa Rica 1888- 1889: 45-64 (page 56, also described as new)
- Forel, A. 1899e. Formicidae. [part]. Biol. Cent.-Am. Hym. 3: 57-80 (page 70, queen described)
- Forel, A. 1908c. Fourmis de Costa-Rica récoltées par M. Paul Biolley. Bull. Soc. Vaudoise Sci. Nat. 44: 35-72 (page 52, worker, male described)
- Wilson, E. O. 2003. Pheidole in the New World: A dominant, hyperdiverse ant genus. Harvard University Press, Cambridge, MA. (page 291, fig. major, minor described)