Pseudoponera succedanea

Pachycondyla succedanea is relatively common, but mostly unknown because it is easily confused with the common Pachycondyla stigma in collections (Mackay and Mackay 2010)

Identification
From Mackay and Mackay (2010): Although types of P. succedanea could not be located and were presumably destroyed during World War II, specimens from Cuba fit Roger’s description and are assumed to be P. succedanea and were used to establish the identity of this species.

The worker of P. succedanea would be most likely confused with that of Pachycondyla cognata, but can be separated by the relatively widely spaced frontal carinae (separated by 0.1 mm or less in P. cognata). It is also more widely distributed than P. cognata, which is known only from Costa Rica and Panamá.

Pachycondyla succedanea workers could also be confused with those of Pachycondyla stigma, but can be separated by the six or seven mandibular teeth (6-toothed in P. stigma) and the clypeus is divided horizontally by a carina (poorly developed carina present in P. stigma). The workers can be distinguished as being smaller (total length usually less then 4 millimeters), having a slightly larger eye (maximum diameter approximately equal to the distance between the eye and anterior edge of head) and especially by the form of the subpetiolar process, which is angulate posteriorly, forming two laminae or flanges (rounded posteriorly in P. stigma).

Separation of the males and females of P. succedanea and P. stigma is difficult. The female of P. succedanea is smaller than that of P. stigma (total length 5.5 - 7 mm). The transverse clypeal carina of P. stigma is not as sharp as it is in the female of P. succedanea. The subpetiolar processes of the female and male of P. succedanea are angulate posteriorly, not completely rounded as in the female and male of P. stigma.

The mandibular furrow is nearly always well developed in the worker and female of P. succedanea, but is poorly developed in the worker and female of P. stigma.

The males can be separated from those of P. stigma by the form of the subpetiolar process, which is angulate as in the workers, not rounded posteriorly as in P. stigma.

The worker and female of P. succedanea could be confused with those of Pachycondyla gilloglyi. They can be easily separated as the mandibles of P. succedanea are smooth and shiny, whereas those of P. gilloglyi are entirely striate. They can also be separated by the six-toothed mandible (usually, sometimes seven-toothed), which has seven teeth in the worker and female of P. gilloglyi. The males of P. succedanea can be easily separated as the depression at the base of the mandible extends nearly the entire length, not just ½ the length as in the male of P. gilloglyi. Additionally the posterior margin of the subpetiolar process of P. succedanea is angulate, not rounded as in the male of P. gilloglyi. The male of P. gilloglyi has deep depressions on the head located laterally and anteriorly to the insertion of the antenna. This region is only slightly depressed in males of P. succedanea.

This species, as well as the other species in the stigma complex, could be easily mistaken to be members of Hypoponera. The two spurs on the posterior tibia can separate them, only one spur occurs in members of Hypoponera. Also the mandibular teeth of the worker and female are well defined, not reduced to denticles as in most species of Hypoponera. Finally the metasternal process is well developed, not nearly absent as in workers and females of Hypoponera.

Specimens in the LACM and INBio were labeled by Dr. Longino as JTL-011, specimens on his website with the same number are P. gilloglyi (thanks to Alex Wild and Jack Longino for pointing this out).

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

Distribution based on Regional Taxon Lists
Neotropical Region: Brazil, Cuba, Dominican Republic, Ecuador, Greater Antilles, Haiti, Honduras.

Habitat
This species is found in a variety of habitats, including tropical rain forest, steep primary forest, a shady ravine, cloud forest, wet mountain forest to hardwood pine valley forest and even a coffee plantation. It is often found near forest edges. Longino (website) reports it from Atlantic lowland rain forest in Costa Rica up to 1200 m. Elevations range from 0 – 2200 meters. (Mackay and Mackay 2010)

Biology
From Mackay and Mackay (2010): These ants nest in rotten wood (logs and stumps) in areas of sandy or clay soils. Rarely, they nest in the soil.

It apparently never nests in the canopy and those found in treefalls move there after the tree has fallen (Longino 1997). Males were collected in nests in March (Costa Rica, Perú), alate females were collected in nests in June (Perú), July and September (Costa Rica) and December (French Guyana). Single, dealate females were collected in March (Jamaica), June (Perú), July (Costa Rica) and October (Venezuela). Four dealate females were collected together without brood or workers (Ecuador), suggesting nests are formed by pleometrosis. Two other dealate females were found together in a rotten log, without brood or workers, further suggesting pleometrosis. Workers from Panamá and Bolivia were extracted from leaf litter. Specimens in Costa Rica inhabit the leaf litter on the forest floor (Longino 1997).

Nomenclature

 *  succedanea. Ponera succedanea Roger, 1863a: 170 (w.q.m.) CUBA. Combination in Pachycondyla (Pseudoponera): Emery, 1901a: 46; in Euponera (Trachymesopus): Emery, 1911d: 85; in Trachymesopus: Kempf, 1960f: 424; in Pachycondyla: Brown, in Bolton, 1995b: 310. Senior synonym of cauta, compressinodis: Mackay & Mackay, 2010: 538.
 * cauta. Euponera (Trachymesopus) cauta Mann, 1922: 8 (w.) HONDURAS. Combination in Trachymesopus: Kempf, 1960f: 423; in Pachycondyla: Brown, in Bolton, 1995b: 303. Senior synonym of compressinodis: Brown, 1963: 7. Junior synonym of succedanea: Mackay & Mackay, 2010: 538.
 * compressinodis. Euponera (Trachymesopus) stigma subsp. compressinodis Borgmeier, 1928b: 62 (w.) BRAZIL. Kempf, 1960f: 425 (q.). Combination in Trachymesopus: Kempf, 1960f: 424. Raised to species: Kempf, 1960f: 424. Junior synonym of cauta: Brown, 1963: 7; of succedanea: Mackay & Mackay, 2010: 538.

Worker
From Mackay and Mackay (2010): The worker is a small (total length about 3.5 - 4.5 mm) dark reddish brown ant. The mandibles have six or seven teeth, often with a smaller tooth between the two basalmost teeth. The clypeus is divided by a horizontal carina, which is especially sharp laterally and overhangs the anteclypeus, and a longitudinal medial carina is present. The medial carina mostly disappears in the middle of the clypeus. The head is relatively small (width 0.84 mm, length 0.92 mm). The eye is small (maximum length 0.05 - 0.10 mm) located about ½ - 2 diameters from the anterior border of the head. The frontal carinae are widely spaced (0.13 mm at the narrowest point). The scapes are relatively short (0.70 mm) and do not reach the posterior lateral corner of the head. The pronotum is swollen at the shoulder, but does not form a carina. The dorsal face of the propodeum is slightly depressed below the level of the mesonotum, the spiracle is elongated to slit-shaped and the posterior lateral edges of the propodeum are angulate, nearly forming carinae. The two faces of the petiole are narrowed toward the apex.

The subpetiolar process is rounded anteriorly and forms two well-developed blunt angles posteriorly. The anterior face of the postpetiole meets the dorsal face at nearly a right angle. The stridulatory file is absent on the second pretergite, as are the arolia. The metasternal process consists of a pair of fang-like slender fingers.

Erect and suberect hairs are present on the mandibles, clypeus, anterior to the eyes on the side of the head, dorsal and ventral surfaces of the head, posterior border, shaft of the scape, dorsum of the mesosoma, dorsum of the petiole, subpetiolar process and all surfaces of the gaster. Most surfaces are covered with golden mostly appressed pubescence.

The mandibles are smooth and glossy with fine striae and scattered punctures. The remainder of the surfaces are finely punctate and dull, the petiole and gaster are weakly shining.

Queen
From Mackay and Mackay (2010): The female is similar to the worker, a small (total length 5 mm) reddish brown specimen. The mandible has 6 - 7 teeth. The clypeus is similar to that of the worker with a medial sharp longitudinal carina and a transverse carina. The sides of the head are nearly straight and parallel; the posterior border is slightly concave. The eye is large (maximum diameter 0.24 mm, located about ¼ - ½ diameter from the anterior edge of the head (side view). The head is relatively small (0.90 mm in width, 0.96 mm long). The scape does not reach or extends slightly past the posterior lateral corner of the head. The ocelli are small (diameter of median ocellus 0.06 mm) but well developed. The medial ocellus is located about 2 - 4 diameters from the lateral ocellus. The pronotum is slightly swollen at the shoulder. The dorsal face of the propodeum is slightly lower than that of the metanotum, the propodeal spiracle is oval-shaped and the posterior lateral edges of the propodeum are nearly formed into a carina. The petiole is narrow when viewed in profile and narrowed towards the apex. The subpetiolar process is rounded anteriorly and strongly angulate posteriorly, the posterior edge consists of two angulate lobes when viewed from below.

Scattered erect hairs are present on most surfaces and the appressed golden pubescence is more abundant than in the worker. Erect hairs are sparse, short (up to 0.2 mm in length, most hairs 0.1 mm in length) and are located on the mandibles, clypeus, scapes, a few are present on the dorsal surface of the head, several are present on the ventral surface of the head, present on the dorsum of the mesosoma, dorsum of the petiole and all surfaces of the gaster. The legs have a few scattered erect hairs. Appressed pubescence is sparse on the head, more abundant on the dorsum of the mesosoma and all surfaces of the gaster.

The mandibles are smooth and glossy with scattered punctures, the remainder of the surfaces is finely punctate and dull.

Male
From Mackay and Mackay (2010): The male is also small (4 mm total length) with tiny edentate mandibles, which are mostly hidden when closed and do not meet in the middle. The eye is large (0.3 mm in greatest diameter) located very close (0.03 mm) to the anterior border of the head. The ocelli are well developed but small. The anterior face of the petiole is nearly straight, the posterior face is broadly rounded with the petiole narrowed towards the apex, the subpetiolar process is similar to that of the worker.

Erect hairs are scattered over the surface, as well as moderately abundant golden appressed pubescence.

Most surfaces are punctate and dull, the sides of the head, the pronotum, the dorsum of the mesosoma and the gaster are weakly shining.

Type Material
lectotype worker, 5 paralectotype workers seen,, 2 cotypes seen, ; 2 “paratype” females seen, (Mackay and Mackay 2010)

Type Locality Information
Cuba; Honduras, Lombardia; Brasil: São Paulo, Raiz da Serra (Mackay and Mackay 2010)

Etymology
The basis of the name of this species is the Latin word succedaneus, meaning following after or substitute for, apparently meaning that this species substitutes the closely related P. stigma. (Mackay and Mackay 2010)