Prionopelta talos Overson & Fisher

Overson, Rick & Fisher, Brian L., 2015, Taxonomic revision of the genus Prionopelta (Hymenoptera, Formicidae) in the Malagasy region, ZooKeys 507, pp. 115-150 : 133

Taxon classification Plantae Hymenoptera Formicidae

Prionopelta talos Overson & Fisher sp. n. Figs 4A, D, 10

Type material.

Holotype, pinned worker, MADAGASCAR, Antsiranana, 9.2 km WSW Befingotra, Rés. Anjanaharibe-Sud, 14.75°S, 49.46667°E, 1260 m, montane rainforest, canopy moss and leaf litter, collection code BLF01217, 11.xi.1994 (B.L. Fisher et al.) (CASC: CASENT0009472). Paratypes, six pinned workers with same data as holotype (CASC: CASENT0009473; CASENT0009474; CASENT0191885; CASENT0339228; CASENT0339229; CASENT0339230).

Diagnosis.

Prionopelta talos can be recognized by the following combination of characters: twelve antennal segments; large globular eye which appears as a half-sphere emerging from the surface of the head, composed of several asymmetrical subunits visible under high magnification; pronounced, tricolored body with a dark brown head, light brown body, and yellow/pale legs; known only from the Anjanaharibe-Sud Reserve in northeastern Madagascar.

Worker measurements

(N=9). HL 0.5-0.53 (0.52); HW 0.39-0.43 (0.41); SL 0.28-0.3 (0.28); WL 0.52-0.62 (0.56); PetL 0.14-0.16 (0.15); PetW 0.21-0.24 (0.23); T1W 0.35-0.38 (0.36); CI 77.07-81.19 (79.06); PI 143.95-163.83 (152.84); SI 67.23-72.59 (69.8).

Worker description.

In full-face view, cephalic foveae become denser medially, so that laterally, foveae are separated by more than the diameter of one fovea, and medially, many foveae are directly adjacent and tend to form longitudinal chains of connected foveae; areas between foveae dark brown and shining; median cephalic area devoid of foveae not swelling above the surface of the surrounding integument and characterized as being widest anteriorly, narrowing posteriorly; apical tooth relatively short in length; eyes largest of all Malagasy Prionopelta , uniformly globular in shape, and under very high magnification, appear to be composed of several subunits which form a conglomerate half-sphere; both large, shallow foveae and small punctures present on pronotum and mesonotum; propodeal surface possesses only large shallow foveae; strong metanotal groove in dorsal view; strong mesopropodeal suture; distinctly tricolored body with uniformly dark brown head, tan mesosoma and gaster, and pale yellow legs and antennae.

Etymology.

The rich brown color of the shiny integument of this taxon inspired the name “Talos”, after the living bronze statue that protected Europa from invaders in Greek mythology. The species epithet is an arbitrary combination of letters, and thus invariant.

Distribution and ecology.

This rare ant is known from a single locality in the Anjanaharibe-Sud Reserve in the province of Antsiranana (Fig. 13). It is found in montane rainforest at an elevation of 1260 meters.

Taxonomic notes.

Prionopelta talos is most likely to be confused with Prionopelta descarpentriesi as it has a similar arrangement of cephalic foveae to some individuals of Prionopelta descarpentriesi (morphotype A). However, Prionopelta talos has distinctly shaped and larger eyes and a striking color pattern that distinguishes it quite easily from all Malagasy congeners.