Brachyponera Emery, 1900a

Eguchi, Katsuyuki, Viet, Bui Tuan & Yamane, Seiki, 2014, Generic Synopsis of the Formicidae of Vietnam (Insecta: Hymenoptera), Part II — Cerapachyinae, Aenictinae, Dorylinae, Leptanillinae, Amblyoponinae, Ponerinae, Ectatomminae and Proceratiinae, Zootaxa 3860 (1), pp. 1-46 : 27-28

Brachyponera Emery, 1900a

Taxonomy. Brachyponera was established as a subgenus of Euponera , and raised to genus by Bingham (1903). It was then synonymized with Pachycondyla by Brown in Bolton (1994), and assigned to the tribe Ponerini ( Bolton 2003) . However, based on a recent molecular phylogenetic analysis ( Schmidt 2013), Schmidt & Shattuck (2014) revived Brachyponera as an independent genus, and placed it under the Odontomachus genus group of the tribe Ponerini .

Morphology. Workers of Vietnamese species have the following features (see also Schmidt & Shattuck 2014):

Worker monomorphic; body (excluding mesopleuron and metapleuron) covered with a dense fine pubescence, and sparsely with standing hairs; head in full-face view subrectangular; preoccipital carina inconspicuous dorsally and laterally; frontal lobes horizontal, relatively small, separated from each other just with a longitudinal sulcus; antennal scrobe absent; median portion of clypeus moderately convex, with anteromedian margin truncate or weakly concave; mandible triangular with ca. 8–10 teeth on masticatory margin; basal portion of mandible with a pit or groove dorsolaterally (but the pit/groove sometimes obsolete); antenna 12-segmented, gradually incrassate from segment III to XII; eye moderate in size, located on side of head relatively close to mandibular insertion; promesonotum forming a dome which is in lateral view distinctly higher than anterior border of propodeal dorsum; promesonotal suture completely separating pronotum from mesonotum; metanotal groove deeply impressed; mesonotum present as a distinct disc well margined anteriorly by promesonotal suture and posteriorly metanotal groove; mesopleuron separated well from mesonotum and metapleuron with distinct sutures, not divided by a transverse groove; propodeum unarmed; orifice of propodeal spiracle small and round; propodeal lobe almost absent; apicoventral part of foretibia without small simple spur behind a large pectinate spur; apicoventral part of mid and hind tibiae with a simple spur in front of a large pectinate spur; outer surface of middle tibia with normal pilosity only; petiole without anterior peduncle; petiolar node squamiform, in lateral view high and thin; subpetiolar process developed, anteriorly without a conspicuous round depression, posteroventrally with an acute angle or a pair of acute angles; girdling constriction between abdominal segments III and IV weak; anteroventral frange/carina of abdominal sternite III (prora) reduced and not externally visible; sting well developed.

Differentiation. The worker of Brachyponera is most similar to that of Pseudoponera , but the latter lacks the basal mandibular pits, deep metanotal groove, and raised promesonotal dome. The worker of small species of Brachyponera are most similar in general appearance to that of Hypoponera , but in the latter the apicoventral part of the mid and hind tibiae lacks a smaller, simple spur in front of the pectinate large spur.

Vietnamese species (6 spp.).

Radchenko (1993a) described Brachyponera mesoponeroides from Vietnam (type locality: Cuc Phuong), and Bolton (1995) and Schmidt & Shattuck (2014) combined the species in Pachycondyla . However, Sk. Yamane’s examination of the type series suggests that the species belongs to Hypoponera . The problem will be solved in a future study.

B. nigrita (Emery, 1895) . Au (Ba Be, Ba Vi, Chua Yen Tu, Cuc Phuong, Tam Dao, Tay Yen Tu), Zry (Cat Tien). B. jerdoni (Forel, 1900) . Rad (Cuc Phuong, nr. Ha Noi).

B. luteipes ( Mayr, 1862) . Rad (Cuc Phuong).

B. sp. eg-2 [cf. B. luteipes ] (Ba Be, Ba Vi, Cuc Phuong, Sa Pa, Tay Yen Tu). B. sp. eg-3 [cf. B. chinensis (Emery, 1895) ] (Ba Vi, Cuc Phuong, Sa Pa, Tam Dao). B. sp. eg-4 [cf. B. nigrita ] (Sa Pa).

Bionomics. Pachycondyla spp. usually occur in well-developed forests and other wooded habitats. They nest in rotting logs and wood fragments, and in litter and soil.