Pheidole embolopyx

Pheidole embolopyx
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Myrmicinae
Tribe:	Attini
Genus:	Pheidole
Species:	P. embolopyx
Binomial name
Pheidole embolopyx Brown, 1968 Type Label

Pheidole embolopyx inhabits rainforest, nesting in pieces of rotting wood buried in litter. Mature colonies contain up to several hundred workers and a single nest queen. Winged queens have been found in March near Manaus. The queens do not use their truncated abdomens to block galleries and nest entrances, as expected (Wilson and Hölldobler 1985). Instead, it is likely that they assume a turtle-like crouching position when threatened, bringing into play the truncated abdomen, flanges on the pronotum, and gelatinous secretions on the front of the head. Wilson and Hölldobler also report the origin of an odor-trail pheromone in the poison gland and an alarm pheromone in the pygidial gland. (Wilson 2003)

At a Glance

• Phragmotic

Identification

See the description in the nomenclature section.

Keys including this Species

• Key to Pheidole diligens group

Distribution

In addition to two localities around Manaus, embolopyx has been recorded from Diamantino, Mato Grosso; from near Puerto Maldonado, Madre de Dios, Peru; and Yasuni National Park in Ecuador. (Wilson 2003)

Latitudinal Distribution Pattern

Latitudinal Range: -0.6258° to -4.994722222°.

North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

• Source: AntMaps

Distribution based on Regional Taxon Lists

Neotropical Region: Brazil (type locality), Ecuador, Peru.

Distribution based on AntMaps

Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.

Biology

Life History Traits

• Mean colony size: 300 (Wilson & Holldobler, 1985; Beckers et al., 1989)
• Foraging behaviour: mass recruiter (Wilson & Holldobler, 1985; Beckers et al., 1989)

Nomenclature

The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

• embolopyx. Pheidole embolopyx Brown, 1968a: 332, figs. 1-7 (s.w.q.) BRAZIL. See also: Wilson, 2003: 189.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.

Description

From Wilson (2003): A unique species of Pheidole, distinguished in the queen by the posteriorly flattened gastral tergites, hence truncated shape of the gaster overall, and the flattened rear surface covered by peculiar short, hooked hairs.

Major: head bicolored with broad dark yellow to light reddish brown arcs over most of the dorsal surface and on the genae and the rest medium brown, as depicted; tip of antennal scape touching head margin two-thirds from level of eye to level of occiput; most of dorsal surface of head foveolate; anterior half of pronotal dorsum transversely carinulate; anterior half of central strip of first gastral tergite shagreened; propodeal spines thick, triangular; postpetiole from above oval.

Minor: head narrowed, with nuchal collar; propodeal spines reduced; margins of pronotal dorsum foveolate; anterior fourth of central strip of first gastral tergite shagreened.

MEASUREMENTS (mm) Paratype major: HW 0.94, HL 1.00, SL 0.74, EL 0.14, PW 0.44. Paratype minor: HW 0.44, HL 0.56, SL 0.72, EL 0.12, PW 0.32.

COLOR Major: head bicolored, as described in Diagnosis above; body light to dark yellow; appendages light brown to brownish yellow.

Minor: concolorous light brown, appendages dark yellow.

Figure. Upper: paratype, major. Lower: paratype, minor. A figure of a paratype queen is also shown (from Brown 1968b). Scale bars = 1 mm.

Holotype Specimen Labels

Type Material

BRAZIL: Ig. Marianil, Rio Branco Rd., 24 km northeast of Manaus. Museum of Comparative Zoology - as reported in Wilson (2003)

Etymology

Gr embolopyx, stopper box, referring to the truncate abdomen of the queen. (Wilson 2003)

References

• Wilson, E. O. 2003. Pheidole in the New World: A dominant, hyperdiverse ant genus. Harvard University Press, Cambridge, MA.
• Albuquerque, E., Prado, L., Andrade-Silva, J., Siqueira, E., Sampaio, K., Alves, D., Brandão, C., Andrade, P., Feitosa, R., Koch, E., Delabie, J., Fernandes, I., Baccaro, F., Souza, J., Almeida, R., Silva, R. 2021. Ants of the State of Pará, Brazil: a historical and comprehensive dataset of a key biodiversity hotspot in the Amazon Basin. Zootaxa 5001, 1–83 (doi:10.11646/zootaxa.5001.1.1).
• Beckers R., Goss, S., Deneubourg, J.L., Pasteels, J.M. 1989. Colony size, communication and ant foraging Strategy. Psyche 96: 239-256 (doi:10.1155/1989/94279).
• Brown, W. L., Jr. 1968 (“1967”). A new Pheidole with reversed phragmosis (Hymenoptera: Formicidae). Psyche (Camb.) 74:331–339.
• Franco, W., Ladino, N., Delabie, J.H.C., Dejean, A., Orivel, J., Fichaux, M., Groc, S., Leponce, M., Feitosa, R.M. 2019. First checklist of the ants (Hymenoptera: Formicidae) of French Guiana. Zootaxa 4674, 509–543 (doi:10.11646/zootaxa.4674.5.2).
• Wilson, E. O. & B. Hölldobler. 1985. Caste-specific techniques of defense in the polymorphic ant Pheidole embolopyx (Hymenoptera: Formicidae). Ins. Soc. 32: 3–22.

References based on Global Ant Biodiversity Informatics

• De Souza Holanda P. M. 2016. Efeitos da variacao do lencol: freatico em assembleias de formigas (Hymenoptera: Formicidae) que vivem na serapilheira na reserva Adolpho Ducke, Manaus, Am. Master's Thesis Universidade Federal do Amazonas, 48 pages.
• Fernández, F. and S. Sendoya. 2004. Lista de las hormigas neotropicales. Biota Colombiana Volume 5, Number 1.
• Franco W., N. Ladino, J. H. C. Delabie, A. Dejean, J. Orivel, M. Fichaux, S. Groc, M. Leponce, and R. M. Feitosa. 2019. First checklist of the ants (Hymenoptera: Formicidae) of French Guiana. Zootaxa 4674(5): 509-543.
• Vasconcelos H. L., J. M. S. Vilhena, W. E. Magnusson, and A. L. K. M. Albernaz. 2006. Long-term effects of forest fragmentation on Amazonian ant communities. Journal of Biogeography 33: 1348-1356.
• Vasconcelos, H.L., J.M.S. Vilhena, W.E. Magnusson and A.L.K.M. Albernaz. 2006. Long-term effects of forest fragmentation on Amazonian ant communities. Journal of Biogeography 33:1348-1356