Neoponera dismarginata

Neoponera dismarginata nests in the ant-plant Cecropia insignis and workers are nocturnal, foraging on vegetation.

Identification
From Mackay and Mackay (2010): Neoponera dismarginata can be separated from most of the others in the foetida species complex in that the malar carina does not reach the eye. This characteristic places this species with Neoponera bugabensis and Neoponera insignis, from which it can be separated by the longitudinal striae in the middle of the clypeus.

Longino (1997) separates an undescribed species as JTL-012, but it is not apparent from the discussion or photographs how it differs from n. dismarginata and is probably con-specific.

Distribution
COSTA RICA (Mackay and Mackay 2010)

Distribution based on Regional Taxon Lists
Neotropical Region: Costa Rica.

Habitat
This species occurs in wet forest at 500 - 1050 meters. (Mackay and Mackay 2010)

Biology
Longino (1997) collected four nests, with no more than two-dozen or so workers. One nest was in a small clearing surrounded by rain forest, the nest was in a thick soft wet dead Piper stem near the ground. A second nest was in a live branch with a diameter of 5 - 10 cm of a small shrub with live and dead hollow stems. The third nest was in a soft rotten stump and in chambers left by a large wood-boring beetle larva. The fourth nest was on a forest trail at the Wilson Botanical Gardens in a Cecropia trunk that had fallen across the trail. The trunk was mostly still alive with a dead apex. The nest was in the internodes at the live to dead transition zone.

Nomenclature

 * . Pachycondyla dismarginata Mackay & Mackay, 2010: 301, figs. 111, 256, 257 (w.) COSTA RICA.
 * Type-material: holotype worker, 3 paratype workers.
 * Type-locality: holotype Costa Rica: Heredia Prov., 16 km. N Volcan Barba, 10°17’N, 845’W, 950 m., 4-15.vii.1986, #1381-S, wet forest, nocturnal forager (J. Longino); paratypes with same data.
 * Type-depositories: MCZC (holotype); INBC, MCZC, WEMC (paratypes).
 * Combination in Neoponera: Schmidt, C.A. & Shattuck, 2014: 151.
 * Status as species: Fernandes, et al. 2014:134 (in key).
 * Distribution: Costa Rica.

Worker
The worker is a moderately large (total length 14 mm) black ant with dark legs. The mandible has approximately 18 teeth; the anterior margin of the clypeus is broadly convex. The malar carina is developed, but does not reach the anterior border of the eye. The eyes are relatively large (maximum diameter 0.69 mm) and are located about one diameter from the anterior margin of the head (side view). The head width is 2.2 mm; the length is 2.9 mm. The scape is relatively long (3.4 mm) and extends more than three funicular segments past the posterior lateral corner. The pronotal shoulder forms a sharp carina, which extends over the sides of the pronotum. The mesosoma is depressed at the metanotal suture, which breaks the sculpture on the dorsum of the mesosoma. The dorsal face of the propodeum is approximately twice the length of the posterior face, the spiracle is slit-shaped. The anterior face of the petiole is vertical and meets the broadly rounded posterior face near the anterior edge. The posterior lateral edges are swollen, but not noticeably and do not form carinae. Erect hairs are abundant on most surfaces, including the scapes, where they are especially long (up to 0.75 mm in length) with approximately 60 present (scape viewed in profile). Many of the hairs on the dorsum of the head are nearly as long (up to 0.48 mm in length), the hairs on the mesosoma, petiole and gaster are similar to those on the dorsum of the head. Appressed golden pubescence is abundant on all surfaces of the head, all surfaces of mesosoma, the posterior face of the petiole and the gaster.

The mandibles are covered with striae and are weakly shining. Most of the surface of the clypeus is covered with longitudinal striae, which are especially obvious in the middle of the clypeus. The dorsum of the head is densely and evenly punctate and dull, the punctures on the mesosoma are finer and some of the surfaces are weakly shining, the side and posterior face of the petiole are finely punctured and weakly shining, the gaster is finely punctate and moderately shining.

Type Material
CR: Pv. Heredia, 16 k N Vol. Barba, 10°17’N 845’W, 950 m. Holotype worker, 3 paratype workers (CWEM, , ).

Etymology
From Latin, dis meaning without and marginata, meaning enclosed with a border, referring to the poorly developed malar carina. William Brown suggested the name.

References based on Global Ant Biodiversity Informatics

 * INBio Collection (via Gbif)
 * Longino J. et al. ADMAC project. Accessed on March 24th 2017 at https://sites.google.com/site/admacsite/
 * Mackay, W.P. and E.E. MacKay. 2010. The systematics and biology of the New World ants of the genus Pachycondyla (Hymenoptera: Formicidae). Edwin Mellen Press Lewiston, NY