Neoponera laevigata

These aggressive ants prey on termites. When they find a termite nest they can create a foraging trail with a column of ants that contains more than 1,000 workers.

Identification
From Mackay and Mackay (2010): Neoponera laevigata workers and females could be confused with those of three other shiny species: Pachycondyla commutata, Pachycondyla marginata and Neoponera carbonaria. Neoponera laevigata can be easily separated from P. commutata and the moderately shiny N. carbonaria by the coarse striae on the side of the propodeum, which are very fine on both of the latter species. The mandibles of N. laevigata are smooth and shining, not dull and striate as in P. commutata and without the longitudinal fold as in P. marginata. The shape of the petiole is very different in N. carbonaria with the anterior face being nearly vertical and the posterior face being convex and meeting the anterior face at an angle and thus not forming a distinct dorsal face. Neoponera laevigata can be separated from P. marginata as the mandible lacks the carina or fold, which separates the inner part of the mandible from the outer part in P. marginata. The mostly shining black surfaces would separate this species from all of the other North American Neoponera.

Distribution
Southern Central America through central South America, Trinidad. (Mackay and Mackay 2010)

Distribution based on Regional Taxon Lists
Neotropical Region: Brazil, Colombia, Costa Rica, Ecuador, French Guiana, Guyana, Panama, Trinidad and Tobago.

Habitat
Specimens have been collected between 350 and 700 meters in wet forest. (Mackay and Mackay 2010)

Biology
From Mackay and Mackay (2010): This species nests in the soil under logs or under heavy leaf litter and sometimes occurs within the log. A male was collected in a nest in September (Panamá). A loose male was collected in March (Costa Rica) and winged females in March and October (Brasil) and December (Costa Rica).

Wheeler (1936) provided details on the biology of this species. He reports that C. Haskins found a column moving to a new nest site on Barro Colorado Island. The column was about 1.5 m in length and about 10 cm wide, containing males and females (August). Emerson found raids three times on Barro Colorado Island at midday during July and September (Wheeler, 1936). The columns were about 6 meters long and a single worker wide. The organized columns contain between 500 - 1700 workers (Downing, 1978). The ants were carrying workers and soldiers of the termites Amitermes beaumonti Banks and Heterotermes tenuis (Hagen), both common in dead wood on the forest floor (Wheeler, 1936). Pachycondyla laevigata is an important predator on the termites Nasutitermes costalis  (Traniello, 1981); and prey on termites in the genera Neocapritermes,   Microtermes and  Coptotermes (Hölldobler and Traniello, 1980) and Speculitermes sp. (Borgmeier, 1959), in addition to the genera mentioned above. Workers are very aggressive and are able to sting.

Workers use a recruitment trail pheromone, which originates from the pygidial gland (Hölldobler and Traniello, 1980) and not, as previously assumed, from the hindgut (Blum, 1966). Baroni Urbani (1993) discussed the evolution of recruitment behavior in P. laevigata.

Nomenclature

 *  laevigata. Ponera laevigata Smith, F. 1858b: 98 (w.) BRAZIL. Wheeler, W.M. 1936d: 162 (q.m.). Combination in Pachycondyla: Mayr, 1886c: 358; in Euponera (Mesoponera): Emery, 1901a: 47; in Termitopone: Wheeler, W.M. 1936d: 159; in Pachycondyla: Brown, in Bolton, 1995b: 306; in Neoponera: Schmidt & Shattuck, 2014: 151. Senior synonym of gagatina: Emery, 1892b: 167; of whelpleyi: Wheeler, W.M. 1936d: 164. See also: Mackay & Mackay, 2010: 414.
 * gagatina. Pachycondyla gagatina Emery, 1890a: 75 (w.) COSTA RICA. [Also described as new by Emery, 1894k: 48.] Junior synonym of laevigata: Emery, 1892b: 167.
 * whelpleyi. Euponera (Mesoponera) laevigata var. whelpleyi Wheeler, W.M. 1922c: 3 (w.) TRINIDAD. Junior synonym of laevigata: Wheeler, W.M. 1936d: 164.

Ponera laevigata

Two worker syntypes in. Labelled “Ega. 58/6.” Acc. Reg.: “1858 no. 6. Amazon (Ega on the Riv.). Purchased of Stevens.”

Worker
From Mackay and Mackay (2010): The worker is usually a moderately sized (total length 5 - 10 mm) shiny black ant with dark brown appendages. The eye is relatively large (0.5 mm maximum diameter) with a diameter about twice as long as the distance between the anterior border of the eye and the anterior border of the head (side view). There is no malar carina. The scape extends slightly past the posterior lateral corner of the head. The pronotal shoulder is swollen, but does not form a carina. The dorsum of the mesosoma is nearly straight, the metanotal suture is poorly developed, but present on the dorsum of the mesosoma. The propodeal spiracle is slit-shaped and the posterior face of the propodeum is separated from the sides of the propodeum by a sharp edge. The petiole is thick when viewed in profile, with the anterior face being slightly concave, the posterior face being convex and the dorsal face being well defined. The dorsal face of the petiole is much broader posteriorly than anteriorly (seen from above). The posterior lateral edges of the petiole are sharp between the sides of the petiole and the posterior face. The anterior face of the postpetiole is slightly concave and meets the dorsal face at an angle.

Erect hairs are abundant on most surfaces, including the sides of the head, the shaft of the scape, the dorsal and ventral surfaces of the head, the dorsum of the mesosoma, the legs (most of the hairs on the tibiae and many on the remainder of the legs are suberect), the dorsum of the petiole and all surfaces of the gaster.

Most of the head is smooth and glossy, but distinct poorly defined striae are present on the dorsum, the mesosoma is mostly smooth and glossy, but the upper half of the mesopleuron and the side of the propodeum have well-developed coarse striae. The dorsal face of the propodeum has a few short (0.3 mm in length) poorly developed striae, the posterior face of the propodeum is smooth and glossy. Most of the petiole and gaster are smooth and glossy.

The workers of this species are polymorphic. They may be as small as 5 mm total length, with all sizes up to the length of the largest worker (total length 10 mm). The smaller workers are less sculptured and the entire head may be smooth and glossy.

Queen
From Mackay and Mackay (2010): The female is a large (total length 13 mm) mostly shiny black ant. The mandible has approximately 11 teeth (basalmost teeth are small and poorly defined) that alternate in size. The anterior margin of the clypeus is broadly convex. The eye is moderately sized (maximum diameter 0.6 mm) located about ⅔ diameter from the anterior margin of the head. The scapes barely reach the posterior lateral corner of the head. The pronotal shoulder is swollen but does not form a well-developed carina. The propodeal spiracle is slit-shaped. The petiole is shaped like that of the worker, moderately thickened when viewed in profile with a slightly concave anterior face and a slightly convex posterior face, which converge dorsally and form a moderately well-developed dorsal face. The subpetiolar process is a lobe, which is angulate ventrally. Erect hairs (up to 0.4 mm in length) are present on the mandibles, clypeus, dorsal and ventral surfaces of the head, sides of the head, posterior margin, scapes, mesosoma, petiole and all surfaces of the gaster, the hairs on the legs are suberect to erect only; appressed pubescence is sparse and only noticeable on the gaster.

The dorsum of the head has longitudinal striae, which diverge posteriorly, the dorsum of the mesosoma is mostly smooth and glossy, as are the side of the pronotum and the anepisternum, the katepisternum and side of the propodeum are striate. The side of the petiole has a little evidence of horizontal striae and is mostly smooth and glossy as is the posterior face. The gaster is nearly completely smooth and glossy.

Male
From Mackay and Mackay (2010): The male is a moderately sized (total length 11 mm) shiny black specimen. The mandibles are tiny and have the oval-shaped depression near the base. The anterior margin of the clypeus is convex with the middle of the clypeus being swollen. The eyes are large (maximum diameter 0.74 mm) occupying more than ½ of the side of the head. The ocelli are relatively small (maximum diameter of the medial ocellus is 0.14 mm). The pronotal shoulder is slightly swollen, the propodeal spiracle is elongated. The shape of the petiole is similar to that of the worker, with the anterior face being nearly straight and the posterior face being convex and converging dorsally, forming a broadly rounded dorsal face. The subpetiolar process is similar to that of the female and only slightly less developed.

Erect hairs (up to 0.3 mm in length) are present on the mandibles, clypeus, all surfaces of the head, dorsum of the mesosoma, dorsum of the petiole and all surfaces of the gaster, most hairs on the legs are nearly erect.

Most surfaces are smooth and glossy as in the worker and female.

Type Material
Two syntype workers seen, ; syntype seen, (Mackay and Mackay 2010)

Type Locality Information
Brasil: Amazonas: Ega; Trinidad, Capara (Mackay and Mackay 2010)

Etymology
The name of this species is from the Latin word laevigatus, meaning smooth, referring to the sculpturing of this species. (Mackay and Mackay 2010)