Pseudoponera cognata

From Mackay and Mackay (2010): Nests are located in rotten logs and stumps and under bark on rotten logs, often near clearings at the edges

Identification
From Mackay and Mackay (2010): The worker and female of Pachycondyla cognata would most likely be confused with those of Pachycondyla succedanea from which it apparently only differs in having the frontal carinae closely spaced (separated at the narrowest point by about 0.07 mm, at least less than 0.10 mm as compared with P. succedanea in which the separation is 0.13 mm or more). Pachycondyla cognata can be separated from the similar P. succedanea and Pachycondyla stigma in having seven mandibular teeth as compared to six teeth in the other two species.

The male of P. cognata can be separated from that of P. succedanea in being somewhat larger (the total length of the male of P. succedanea is about 4 mm) and in not having the subpetiolar process angulate posteriorly. The separation of P. cognata from males of P. stigma is more difficult (possibly due to the small amount of material that is available). The subpetiolar process of P. cognata is deeper (0.11 mm) than that of P. stigma (0.09 mm). The apex of the petiole is sharper than it is in P. stigma. Otherwise the males of the three species (P. cognata, P. stigma and P. succedanea) are very similar.

Members of P. cognata could be confused with those of the genus Hypoponera, but differ in having two tibial spurs on the posterior tibia of P. cognata as compared with a single tibial spur in workers of Hypoponera.

The mandibles of workers and females of P. cognata are nearly always covered by striae, specimens from the Estación Biológica La Selva in Costa Rica tend to have smooth and glossy mandibles.

Distribution
COSTA RICA, PANAMA, COLOMBIA (Mackay and Mackay 2010)

This taxon was described from Costa Rica.

Habitat
These ants are found in tropical rain forest and mature lowland rain forest at 450 m and 600 m (Longino, website) up to 1150 m in elevation. (Mackay and Mackay 2010)

Nomenclature

 *  cognata. Ponera cognata Emery, 1896g: 56 (w.q.) COSTA RICA. Mackay & Mackay, 2010: 252 (m.). Combination in Pachycondyla (Pseudoponera): Emery, 1901a: 46; in Euponera (Trachymesopus): Emery, 1911d: 85; in Trachymesopus: Kempf, 1960f: 423; in Pachycondyla: Brown, in Bolton, 1995b: 304.

Worker
From Mackay and Mackay (2010): The worker is a relatively small (total length approximately 5 mm) reddish brown opaque ant. The mandibles have 7 teeth and the clypeus has a well-defined horizontal transverse sharp ridge, which is only interrupted in the middle and separates the anteclypeus from the postclypeus. The frontal carinae are located close together and are separated by approximately 0.07 mm (at least less than 0.1 mm) at the narrowest point. The eyes are relatively small (maximum diameter 0.1 mm excluding the surrounding ocular ring) and located approximately one diameter from the anterior edge of the head (side view). The scapes are relatively short and fail to reach the posterior lateral corners of the head by nearly the first funicular segment. The dorsum of the mesosoma is nearly straight, but slightly depressed at the metanotal suture, which interrupts the sculpture on the dorsum of the mesosoma. The propodeal spiracle is oval in shape, but nearly as long as wide. The petiole is relatively narrow and tapered to the apex. The sub-petiolar process is rounded anteriorly and angulate posteriorly with two distinct angles. The anterior face of the postpetiole meets the dorsal face at a right angle. The stridulatory file on the pretergite is absent as are the arolia.

Erect hairs are sparse on the worker and scattered on most surfaces, including the scapes. Most surfaces are punctate and dull and only the mandibles, the petiole and the gaster are moderately shining.

Queen
From Mackay and Mackay (2010): The female is slightly larger than the worker (total length 6 - 7 mm) dark reddish brown with lighter colored appendages. The mandible has 7 teeth, the transverse horizontal carina is well developed on the clypeus and overhangs the anteclypeus; the longitudinal carina is also present. The eyes are large (maximum diameter 0.35 mm) located less than ⅓ diameter from the anterior edge of the head (side view). The ocelli are small (maximum diameter of median ocellus 0.06 mm). The scape is narrow basally and thickened apically and the scape does not reach the posterior lateral corner of the head. The pronotum is swollen on the shoulder, but does not form a carina.

The side of the propodeum is slightly depressed, apparently for the reception of the posterior femur. The petiole is narrow when viewed in profile with a straight or slightly concave anterior face and a convex posterior face. The subpetiolar process is lobe-shape or rectangular-shaped, but with a distinct, but poorly defined posterior angle. The anterior face of the postpetiole forms nearly a right angle with the dorsal face. Erect hairs are scattered on the mandibles, dorsal and ventral surfaces of the head, scape, posterior margin of the head, on the mesosoma, petiole and gaster, the hairs on the legs are erect or suberect. Appressed golden pubescence is short, but abundant on the head, dorsum of the mesosoma and gaster.

The mandibles of the female are finely striate and moderately glossy, with an oblique furrow; the dorsum of the head is finely punctate and dull, the dorsum of the mesosoma has similar sculpture, the sides of the mesosoma have indistinct striae. The petiole is moderately shining (front and sides) to strongly shining (posterior face) with poorly defined striae. The gaster is finely punctate or coriaceous and moderately shining.

Male
From Mackay and Mackay (2010): The male (undescribed) is a small (total length 5 mm) dark brown ant. The anterior margin of the clypeus is weakly convex and the surface of the clypeus is swollen when viewed in profile. The head length and width are both 0.8 mm. The eyes are relatively small (maximum diameter 0.4 mm) and located nearly one diameter from the lateral ocellus. The ocelli are relatively small (diameter of the median ocellus 0.09 mm); the medial ocellus is located approximately one diameter from the lateral ocellus (diameter 0.1 mm). The Mayrian furrows are weakly developed, but present and do not connect in the middle of the scutum. The parapsidal sutures are well developed. The propodeal spiracle is circular-shaped. The petiole is nearly triangular shaped with both faces sloping and forming a moderately sharp apex. The subpetiolar process consists of a rounded blunt process.

Erect hairs are present on the dorsum of the clypeus, head, posterior margin of the head, mesosoma, petiole and gaster, the hairs on the legs are suberect to erect on most surfaces, including the tibiae. Golden appressed pubescence is present on the head, mesosoma and gaster.

Most surfaces are coriaceous or finely punctate and only weakly shining.

Type Material
Lectotype worker seen,, paralectotype female seen,. (Mackay and Mackay 2010)

Type Locality Information
Costa Rica, Jiménez and Suerre (Mackay and Mackay 2010)

Etymology
The name of this species is derived from the Latin word cognatus, meaning “related to”. Emery considered it to be closely related to P. stigma. (Mackay and Mackay 2010)