Neoponera cavinodis

From Mackay and Mackay (2010): Samples have been collected with dealate females when fogging the tropical canopy. Winged females were collected in June and a winged male was collected between January and July (Ecuador, in a tree fogging experiment). Otherwise nothing is known of this unusual species.

Identification
From Mackay and Mackay (2010): The unusual form of the petiole of the worker and female of P. cavinodis would separate this species from all of the others. Two similar species, Pachycondyla goeldii and Neoponera carinulata, have the posterior face of the petiole noticeably convex and the highest point is near the middle of the dorsal face. Other species of the crenata species complex lack the strongly concave posterior face of the petiole.

Pachycondyla cavinodis is most similar to Pachycondyla oberthueri, but can be easily separated as the lower part of the posterior face of the petiole of P. oberthueri is strongly convex and the posterior edge does not overhang the posterior face (but is weakly concave near the apex). Mann (1916) compares P. cavinodis to Pachycondyla crenata, although they have little in common other than both belonging to the crenata species complex. They can be instantly separated even with the unaided eye by the concave posterior face of the petiole of P. cavinodis, which is convex or at most straight in P. crenata. Neoponera bucki has a similar petiole, but lacks the malar carina.

Mann (1916) considered P. cavinodis to be near Pachycondyla luteola. Actually they have little in common. The worker of P. luteola is pale yellowish brown, versus the darker brown P. cavinodis (the female of P. luteola is dark brown). The posterior face of the petiole is convex in P. luteola. The malar carina is nearly absent in P. luteola, whereas it is well developed in P. cavinodis. The posterior border of the head of both the worker and female of P. luteola is strongly concave, not nearly straight as in P. cavinodis. Thus there is no likelihood that the two species would be confused or even be considered to be closely related.

The male of P. cavinodis was not associated with workers or females, but was collected from the same fogging experiment as a worker. The shape of the petiole suggests that it is conspecific with the worker and should allow it to be easily recognized and separated from the males of most of the other species.

Distribution
PANAMA, ECUADOR, PERU, GUYANA, BRASIL (Mackay and Mackay 2010)

Distribution based on Regional Taxon Lists
Neotropical Region: Brazil, Ecuador, Guyana, Panama, Peru.

Habitat
This species has been collected in mature terra firme forest at 200 m elevation. (Mackay and Mackay 2010)

Nomenclature

 *  cavinodis. Neoponera (Neoponera) cavinodis Mann, 1916: 414, pl. 2, fig. 14 (w.) BRAZIL. Wheeler, G.C. & Wheeler, J. 1971b: 1205 (l.); Mackay & Mackay, 2010: 238 (q.m.). Combination in Pachycondyla: Brown, in Bolton, 1995b: 304; in Neoponera: Schmidt & Shattuck, 2014: 151.

Worker
From Mackay and Mackay (2010): The worker is a small (total length 8 mm) dark brown specimen that can be easily recognized as the posterior face of the petiole is strongly concave, the anterior face is convex and broadly rounded and the petiolar node ends in a point posteriorly. The anterior margin of the clypeus forms a medial angle; the eyes are located anteriorly on the head at less than one diameter from the anterior margin of the head. The malar carina is well developed and sharp. The scape is elongate and extends nearly the first three funicular segments past the posterior lateral corner. The carina on the pronotal shoulder is sharp and well developed. The region between the dorsal and posterior faces of the propodeum is angulate. The propodeal spiracle is slit-shaped.

Erect hairs are present on most surfaces, including the dorsum and ventral surface of the head, scapes, dorsum of the mesosoma, all surfaces of the legs, dorsum of the petiole and all surfaces of the gaster; fine silver appressed pubescence is present on most surfaces, especially the dorsum of the head and the dorsum of the gaster.

The dorsum of the head is finely punctate as is the dorsum of the mesosoma, the side of the mesosoma is mostly coriaceous and partially shining, the dorsum of the petiole and dorsum of the gaster are covered with fine punctures.

The lectotype specimen is medium brown with yellowish brown legs.

Queen
From Mackay and Mackay (2010): The female (undescribed) is a small (total length 8 mm) dark reddish brown ant with brown appendages. The mandible has approximately 13 teeth. The anterior margin of the clypeus is convex and angulate medially with a lobe which overhangs the anteclypeus. The head length is 2.05 mm; the head width is 1.68 mm. The malar carina is well developed and extends past the anterior border of the eye, which has a maximum diameter of 0.56 mm. The sides of the head are slightly narrowed anteriorly and the posterior border is nearly straight or convex. The pronotal shoulder forms a sharp carina, which slightly overhangs the side of the pronotum. The propodeal spiracle is elongated. The petiole is shaped like that of the worker with a broadly convex anterior face and concave posterior face, which forms a dorsal angle, which overhangs the posterior face.

Erect hairs are abundant on most surfaces including the mandibles, clypeus, dorsal and ventral surfaces of the head, posterior margin of the head, sides of the head, scapes, dorsum of the mesosoma, petiole and all surfaces of the gaster; the hairs on the legs are mostly suberect. Golden appressed pubescence is abundant on the head, dorsum of the mesosoma and all surfaces of the gaster.

The mandibles are finely striate and weakly shining, the dorsum of the head is densely punctate, the dorsum of the mesosoma is sparsely punctate and the sides of the mesosoma are similar with most surfaces moderately to strongly shining. The side of the petiole is punctate as is the dorsal face, the posterior face is smooth and glossy and gaster has scattered punctures and is moderately shining.

Male
From Mackay and Mackay (2010): The male (undescribed) is a small (total length 8 mm) medium brown specimen with a yellowish brown head, pronotum, mesopleuron and appendages. The clypeus is swollen anteriorly, with the anterior margin broadly convex. The head length is 1.13 mm; the head width is 0.91 millimeters. The malar carina is absent. The eye is large (maximum diameter 0.66 mm, seen from the side) with the posterior edge extending to approximately ⅓ diameter from the lateral ocellus. The median ocellus is large (maximum diameter 0.16 mm), located approximately 1 diameter from the lateral ocellus (maximum diameter 0.16 mm). The pronotal shoulder lacks a carina, the Mayrian furrows are well developed, but do not connect medially; the propodeal spiracle is slit-shaped. The anterior face of the petiole is convex and broadly rounded and meets the posterior face near the posterior edge of the petiole, but does not form an angle as in the worker and female. The posterior face is slightly concave. The subpetiolar process consists of a broad large anterior angle followed by a concave area and a small broadly rounded angle posteriorly. The stridulatory file on the second acrotergite is well developed. The arolium between the tarsal claws is well developed.

The dorsal and ventral surfaces of the head have several erect hairs as does the posterior border and the clypeus. The mesosoma is covered with short (up to 0.2 mm in length) erect hairs, erect hairs are abundant on the node of the petiole and all surfaces of the gaster; the coxae and femora have several erect hairs as do the tibiae, with most hairs on the tibiae being shorter than the diameter of the tibiae; silver appressed pubescence is moderately abundant on all surfaces.

The dorsum of the head is finely punctate, moderately shining, the dorsum of mesosoma is more coarsely punctate, but shining, especially the pronotum and the mesopleuron, the petiole is punctate and weakly shining and gaster is densely, but finely punctate and moderately shining.

Type Material
holotype Rondônia designated, (Mackay and Mackay 2010)

Type Locality Information
Brasil: Puerto Velho (Mackay and Mackay 2010)

Etymology
The species name comes from Latin, with cavus meaning hollowed out and nodus, meaning swelling, referring to the hollowed out posterior face of the petiolar node. (Mackay and Mackay 2010)