Psalidomyrmex

A small genus (six described species) restricted to central and western Africa. They are cryptic foragers, and at least one species is a specialist predator of earthworms. The latest generic revision is by Bolton (1975b) and there is an updated list of species and a species key presented in Bolton & Brown (2002). Species of Psalidomyrmex nest in rotten wood, beneath logs, or directly in the ground and hunting is generally performed solitarily (Bolton, 1975b). All species seem to be specialised predators of earthworms. Workers are able to capture worms as long as 10 cm (Dejean et al., 1999).

Identification
Schmidt and Shattuck (2014) - Psalidomyrmex workers and queens are readily identified by their unique mandibular structure (mandibles falcate to subtriangular, with broadly rounded basal angles and an attenuated apical tooth) and by their projecting labral lobe, both of which are autapomorphic within the Ponerinae. Other diagnostic characters include the hypertrophied frontal lobes, longitudinal groove on the propodeal dorsum, and large lateral metapleural gland orifice. Psalidomyrmex is most similar to the other members of the Plectroctena genus group, including Loboponera and Plectroctena itself. In addition to lacking the two autapomorphies of Psalidomyrmex already mentioned, these genera differ from Psalidomyrmex in having longitudinal dorsal grooves in the meso- and metafemora and distinct propodeal lamellae.


 * Key to African and Malagasy Genera of Ponerinae

Distribution
Psalidomyrmex is restricted to central and western Africa, ranging from Sierra Leone to Kenya and as far south as Gabon and the Democratic Republic of Congo (Bolton, 1975b; Bolton & Brown, 2002).

Species richness
Species richness by country based on regional taxon lists (countries with darker colours are more species-rich). View Data



Biology
Schmidt and Shattuck (2014) - Very little is known about the ecology and behavior of Psalidomyrmex. They nest in rotting logs, in the soil beneath rotting logs (Bolton, 1975b), or in deserted termitaries (Déjean et al., 1996, 1997), and workers forage individually in rotting wood or in leaf litter (Bolton, 1975b). Psalidomyrmex procerus is known to be a specialist predator of earthworms (Lévieux, 1982; Déjean et al., 1992), and though the feeding habits of the other species is unknown, it seems likely that they too may feed on earthworms, given the apparently specialized mandibular structure of the genus.

Nomenclature

 *  PSALIDOMYRMEX [Ponerinae: Ponerini]
 * Psalidomyrmex André, 1890: 313. Type-species: Psalidomyrmex foveolatus, by monotypy.

Description
Schmidt and Shattuck (2014):

Worker
Medium to large (TL 9.0–16.0 mm; Bolton, 1975b) ants with the standard characters of Ponerini. Mandibles falcate to subtriangular, with rounded basal angles, a long apical tooth and a basal groove. Labrum projecting anteriorly beyond the anterior clypeal margin as a lobe. Frontal lobes large, expanded laterally and closely approximated. Eyes of moderate size, located anterior to head midline. Metanotal groove vestigial. Propodeum broad dorsally, with a shallow longitudinal groove dorsally. Propodeal spiracles round. Metapleural gland orifice very large, opening laterally. Metatibial spur formula (1p). Petiole nodiform. Anteroventral articulatory surface of petiole long and broad, with a narrow median V-shaped longitudinal groove. Gaster with a strong constriction between A3 and A4. Head and body with moderate sculpturing (variously punctate, foveolate or striate), with very sparse pilosity and no pubescence. Color reddish brown to black.

Queen
Similar to workers but slightly larger, alate and with ocelli.

Male
See description in Bolton (1975b).

Larva
Described for Psalidomyrmex procerus by Wheeler & Wheeler (1964).