Neoponera apicalis

Identification
From Mackay and Mackay (2010):

There are only a few species of Pachycondyla in which the workers lack erect hairs on the dorsum of the mesosoma (Pachycondyla magnifica, Pachycondyla bucki, Pachycondyla apicalis, Pachycondyla obscuricornis and Pachycondyla verenae). Of these species, three have very large eyes, which occupy more than ⅓ of the side of the head (P. apicalis, P. obscuricornis and P. verenae). Pachycondyla apicalis can nearly always be separated from the other two species with large eyes, as at least part of the funiculus of the worker, female and even the male is yellow (or pale brown in the male). This characteristic can be easily seen in the field. Pachycondyla apicalis could be confused with the closely related P. cooki, which also has a yellow-tipped funiculus, but P. cooki also has abundant erect hairs on the dorsum of the mesosoma, which are lacking in P. apicalis. The funiculi of the worker, female and male of P. verenae (and the worker of P. obscuricornis) are usually dark brown, but may be reddish brown near the apex, but are never yellow. The posterior lateral edge of the petiole of P. apicalis is broadly rounded into the posterior face, whereas it is mostly angulate in the petiole of P. verenae. This characteristic will also separate the females of the two species. The males are quite different, as the male of P. verenae is completely dark brown, (including the entire antennae) and the side of the petiole lacks the rugae found on the petiole of the male of P. apicalis. The last few segments of the funiculus of workers and females of P. fauveli from Colombia and Ecuador are often yellow and it looks similar to workers of P. apicalis. They can be instantly recognized by the moderately abundant erect hairs on the dorsum of the mesosoma of P. fauveli, which are mostly or completely lacking in P. apicalis.

Rarely P. apicalis may have hairs on the dorsum of the mesosoma and petiole, which may cause confusion with the Amazonian P. cooki. Such specimens of P. apicalis can be distinguished as the head is dull and covered with small punctures, not distinctly striate as it is in Pachycondyla cooki.

A specimen (NHMB) differs from the typical form in having a longer petiole (1.3 mm vs. 1.2 mm in the usual specimens), which is also shorter (1.6 mm from bottom margin, versus 1.65 in usual specimens), but is considered to be P. apicalis.

Wild (2005) discusses geographic variation in the shape of the petiole, number of erect hairs, especially on the gaster and the size of the eye.

Range
MEXICO, GUATEMALA, HONDURAS, NICARAGUA, COSTA RICA, PANAMA, COLOMBIA, ECUADOR, VENEZUELA, TRINIDAD, FRENCH GUIANA, SURINAME, BRAZIL, BOLIVIA (Mackay and Mackay 2010)

This taxon was described from South America.

Habitat
This species is common in primary and secondary wet tropical forests and in medium elevation rain forests (150 - 1500 m). It even occurs in coffee plantations and second growth thorn forest (Wild, 2005). Wild (2005) lists the elevations from sea level to 1600 meters with a mean of 642 meters. This species has been collected in caves near the entrances (Reddell and Cokendolpher, 2001). This is one of the most common species in the tropical forest in the state of Veracruz, México, but is not found in the adjacent grassland (Quiroz-Robledo and Valenzuela-González, 1995). (Mackay and Mackay 2010)

Abundance
Very common.

Biology
From Mackay and Mackay (2010):

Pachycondyla apicalis nests in rotten wood (Levings and Franks, 1982; Dietemann and Peeters, 2000; Baena, 1993; Longino, website), including logs and stumps, or in the soil (Levings and Franks, 1982). A nest was found in root mass of a large Ficus within one meter of the ground (Fresneau, 1985). Another nest was found in bamboo (Guadua sp.) (Wild, 2005). Nests have about 30 (Mann, 1916) to 90 workers (Fresneau, 1985). Males and females were present in nests in January (Costa Rica) and May (Panamá). Dealate females have been captured in March (Costa Rica), June (Panamá), July (Costa Rica) and August (Ecuador, Venezuela). Winged males were collected in January to July (Ecuador, tree fogging) and November (Perú).

Workers are individual foragers and apparently not optimal foragers (Goss et al., 1989), but show a high degree of regional specialization that persists for extended periods of time (Fresneau, 1985). There is no recruitment and tandem running only occurs during nest translocation (Fresneau, 1985). They are very active predators and are often captured on the ground or in pitfall traps. These ants are opportunist predators on termites in the genera Constricto-termes and Nasutitermes (Mill, 1982a); and an important predator on Nasutitermes costalis (Traniello, 1981). Foragers were attracted to tuna bait and were found feeding on a dead Iguana iguana, the large green tropical lizard. Workers carry droplets of food in their mandibles, which they share with the other members of the nest, including the larvae (Dejean and Corbara, 1990a). When they feed smaller larvae they hold the droplet and the larva at the same time and deposit the droplet on the body of the larger larvae.

Foragers disperse the seeds of Calathea ovandensis (Marantaceae) approximately 9 meters from where they were collected (Horvitz and Schemske, 1986a, 1986b). Foragers collect diaspores on the forest floor (Pizo and Oliveira, 2000).

Colony odor is apparently produced in the postpharyngeal gland and transferred to the epicuticle by allogrooming and not by trophallaxis (Soroker et al., 1998, 2003). Lachaud and Fresneau (1987) discuss the social regulation following an experimental sociotomy of a colony. Workers develop a dominance order with a single dominant worker, which lays eggs and maintains her position by physical attack on others and the destruction of eggs laid by sub-ordinates (Oliveira and Hölldobler, 1990). They respond and attempt to escape from the collector and have a painful sting. The venom has a bitter taste due to the presence of cyclic dipeptides of leucine and phenylalanines (López and Morgan, 1997). The function of the venom may thus be both defensive and offensive. The mandibular glands contain δ-decalactone and benzalde-hyde (López and Morgan, 1997).

Caetano (1988) described the digestive and excretory system of the worker. Hölldobler and Engel-Siegel (1982) described the tergal and sternal glands of the male.

Pachycondyla apicalis is mimicked by the spider Castianeira memnonia  (Reiskind, 1977; Wild, 2005).

Worker
Mackay and Mackay (2010): This species is easily recognized, even in the field, as being a common moderately large (total length ~ 12 mm) black ant with a yellow-tipped funiculus. The eyes are large with a diameter greater than the distance to the insertion of the mandible and occupy about ⅓ of the length of the side of the head (side view). A well-defined malar carina is present between the anterior edge of the eye and the clypeus. The mesosoma is weakly depressed at the metanotal suture; the petiole is thick and cuboidal-shaped when viewed in profile. The stridulatory file is present on the dorsum of the gaster, but is poorly defined. The metasternal process consists of two widely spaced triangular lobes, with horizontal striae on the inner posterior surface. Specimens from Colombia often have metasternal lobes similar to those of P. verenae with the striae on the posterior face being more oblique and the inner distal half of the process being concave.

Erect hairs are sparse and mostly restricted to the head and the gaster; a few suberect hairs are present on the flexor surface of the distal half of the tibiae. The mandibles are moderately shining, with fine striate, the remainder of the ant is densely, but finely punctate with all surfaces dull.

This common attractive ant is mostly black, except for the yellow distal half of the funiculus.

Female
Mackay and Mackay (2010): The female is a large (total length 13 mm) dull black ant with approximately the last five funicular segments yellow. The remainder of the ant is similar to that of the workers, except three ocelli are well developed and the mesosoma is adapted for flight.

Male
Mackay and Mackay (2010): The male (undescribed) is a dark ferrugineous brown ant of moderate size (total length 10 mm) with the entire funiculus being pale brown (flesh-colored). The length of the head is 1.5 mm, the width (posterior to the eye) is 1.2 mm, the scape is short (0.35 mm) and the eye is large (0.95 mm). The shape of the petiole is similar to that of the worker, but differs in having the side of the petiole covered with irregular rugae.

Erect hairs are sparse with a few present on the clypeus, dorsum of the head, medial part of pronotum, dorsum of the mesosoma and ventral surface (a few hairs are present on the posterior dorsal surface) of the gaster.

Most surfaces of the male are dull and finely punctured with poorly defined striae. The sculpture of the side of the petiole is characteristic of this species, covered with coarse wrinkle-like rugae.

Type Locality Information
South America.

Etymology
The name of this species comes from Latin, apicalis meaning “pertaining to the apex”, a reference to the yellow color on the tip of the antenna. (Mackay and Mackay 2010)