Pseudomyrmex satanicus

Identification
Ward (1993) - The foregoing diagnosis will allow discrimination of P. satanicus workers from those of the closely related Pseudomyrmex spinicola; queens can be recognized by size alone (HL > 1.65, HW > 1.20). P. satanicus can be distinguished from the remaining members of the P. ferrugineus group by the emarginate, laterally angulate median clypeal lobe of the worker and the large size of the queen.

Distribution
Costa Rica and Panama.

This taxon was described from Panama.

Biology
Ward (1993) - P. satanicus is a forest species restricted to a few localities in central Panama where its host plant, Acacia melanoceras, grows. Both the ant and plant are intolerant of forest clearance and are considered vulnerable to extinction (Janzen 1974). The ant is polygynous, with 5-20 or more queens per colony, and the workers are particularly aggressive, even for acacia-ants (Wheeler 1942; Janzen 1974). See Janzen (1974:43-53) for additional details on P. satanicus and its host plant.

Nomenclature

 *  satanicus. Pseudomyrma satanica Wheeler, W.M. 1942: 174, pl. 47, fig. b (w.q.m.) PANAMA. Combination in Pseudomyrmex: Kempf, 1972a: 223. See also: Ward, 1993: 149.

Worker
Ward (1993) - measurements (n=15). —HL 1.16-1.36, HW 1.10-1.26, MFC 0.035-0.057, CI 0.90-0.97, REL 0.45-0.50, REL2 0.48-0.52, OOI 0.92-1.67, VI 0.69-0.78, FCI 0.030-0.049, SI 0.45-0.49, SI2 0.88-1.00, NI 0.63-0.68, PLI 0.47-0.54, PWI 0.46-0.63, PPWI 1.35-1.54.

Similar to Pseudomyrmex spinicola (q.v.) except as follows. Larger (HW > 1.09), head broader (CI > 0.88) with straight or slightly concave posterior margin and subangulate posterolateral corners. (The posterior margin of the head approaches this condition in some P. spinicola workers but these have much smaller, more elongate heads, HW < 1.10, CI < 0.90.) Median clypeal lobe narrower (CLW/HW 0.20-0.22). Palp formula 4,3. Head with pronounced pit-like impression below the median ocellus (absent or poorly developed in P. spinicola). Metanotal groove better developed, longer. Petiole tending to be more slender, with less distinct posterolateral corners (this characteristic seen in some workers of P. spinicola, especially individuals from Panama). Body pubescence averaging thicker than in P. spinicola. Dark brown in color, mandibles and appendages lighter.

Type Material
Ward (1993) - Syntype workers, queen, male, Rio Agua Salud, Canal Zone, Panama (W. M. Wheeler) [Examined]. One MCZC syntype worker here designated LECTOTYPE.