Mesoponera Emery, 1900b

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 : 36-37

Mesoponera Emery, 1900b

Taxonomy. Mesoponera was first 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 Mesoponera 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 covered with a dense fine pubescence, and sparsely with standing hairs; head in full-face view subrectangular; preoccipital carina very fine dorsally; frontal lobes horizontal, small and narrow, separated from each other just with a longitudinal sulcus; antennal socket in full-face view only partly concealed by frontal lobe; antennal scrobe absent; median portion of clypeus with a median longitudinal ridge; anteromedian margin of clypeus convex and with a blunt median point; mandible elongate-triangular, very long, with ca. 15 teeth on masticatory margin; basal portion of mandible without a pit dorsolaterally; 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 in lateral view with a continuous round dorsal outline; promesonotal suture completely separating pronotum from mesonotum; metanotal groove deep; 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 round and small; propodeal lobe almost absent; apicoventral part of foretibia usually with a 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; subpetiolar process elongate rectangular; girdling constriction between abdominal segments III and IV relatively weak; abdominal sternite III with a distinct anteroventral flange beneath helcium; sting well developed.

Differentiation. The worker of Mesoponera is somewhat similar to that of Brachyponera , but in the latter the basal portion of mandible has a pit or groove dorsolaterally (but the pit/groove is sometimes obsolete), mandible is not elongate, and prora is reduced and notexternally visible.

Vietnamese species (2 spp.).

M. melanaria ( Emery, 1893) . Zry (Cat Tien).

M. s p. eg-1 [cf. M. papuana (Viehmeyer, 1914) ] (Phu Quoc, Van Ban).

Bionomics. Mesoponera sp. eg-1 occurs in well-developed forests, and nest in rotting logs and wood fragments.