Pheidole fiorii

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)

Identification
See the description in the nomenclature section.

Distribution
Atlantic slope and montane Costa Rica to 950 m. (Wilson 2003)

Distribution based on Regional Taxon Lists
Neotropical Region: Costa Rica, Nicaragua, Panama.

Biology
Black (1987) - Pheidole fiorii colonies make carton nests of soil and vegetal fragments on the undersides of leaves. Entrances are poorly defined,usually one large and many smaller ones. Nests consist of several layers, each of which has many chambers. Small seeds of several plant families are found.

A colony from Costa Rica (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queen, 646 workers, 67 soldiers, 6 gynes, larvae and over 400 pupae (workers 414, soldiers 5, gynes 17) (C. Peeters unpublished).



Worker
Minor

Images from AntWeb
Major

Nomenclature

 *  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.

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.

Similar to Pheidole ajax, Pheidole hector, Pheidole jaculifera and Pheidole lourothi, 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 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.'''

Type Material
Jimenez, Costa Rica; collected by Anastasio Alfaro. and  - as reported in Wilson (2003)

Etymology
Named after Andrea Fiori. (Wilson 2003)

References based on Global Ant Biodiversity Informatics

 * Branstetter M. G. and L. Sáenz. 2012. Las hormigas (Hymenoptera: Formicidae) de Guatemala. Pp. 221-268 in: Cano E. B. and J. C. Schuster. (eds.) 2012. Biodiversidad de Guatemala. Volumen 2. Guatemala: Universidad del Valle de Guatemala, iv + 328 pp
 * Emery C. 1890. Studii sulle formiche della fauna neotropica. Bull. Soc. Entomol. Ital. 22: 38-8
 * Gomez V. E. S., and G. Z. González. 2007. Catalogo de Las Hormigas Presentes en El Museo de Historia Natural de la Universidad del Cauca. Popayán : 1-58.
 * Jeanne R. J. 1979. A latitudinal gradient in rates of ant predation. Ecology 60(6): 1211-1224.
 * Kempf, W.W. 1972. Catalago abreviado das formigas da regiao Neotropical (Hym. Formicidae) Studia Entomologica 15(1-4).
 * Longino J. T. L., and M. G. Branstetter. 2018. The truncated bell: an enigmatic but pervasive elevational diversity pattern in Middle American ants. Ecography 41: 1-12.
 * Longino J. T., and R. K. Colwell. 2011. Density compensation, species composition, and richness of ants on a neotropical elevational gradient. Ecosphere 2(3): 16pp.
 * Longino J. et al. ADMAC project. Accessed on March 24th 2017 at https://sites.google.com/site/admacsite/
 * Maes, J.-M. and W.P. MacKay. 1993. Catalogo de las hormigas (Hymenoptera: Formicidae) de Nicaragua. Revista Nicaraguense de Entomologia 23.