Harpegnathos Jerdon, 1851

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 : 33

Harpegnathos Jerdon, 1851

Taxonomy. The genus Harpegnathos is assigned to the tribe Ponerini ( Bolton 2003) .

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

Worker monomorphic; head in full-face view subrectangular; preoccipital carina present dorsally and laterally; frontal lobe horizontal, almost completely concealing antennal socket; antennal scrobe absent; anteromedian margin of clypeus almost straight; posteromedian part of clypeus relatively narrowly inserted between frontal lobes; labrum with a median process that is visible in full-face view; mandible with an elongate and linear blade which has two rows of many small teeth; ventral part of base of each mandibular blade forming a large extensional triangular flange; antenna 12-segmented, filiform; eye extremely large, located on anteriormost part of side of head; small median and lateral ocelli present; mesosoma in lateral view with an almost gently arched dorsal outline; promesonotal suture completely separating pronotum from mesonotum; mesopleuron not separated from mesonotum by a suture, and feebly separated from metapleuron by a faint suture; metanotal groove absent; propodeum unarmed; orifice of propodeal spiracle elliptical or slit-like; propodeal lobe inconspicuous; inner curvature of pretarsal claws equipped with a tooth in addition to the pointed apex; apicoventral part of foretibia with a small simple spur behind a large pectinate spur; apicoventral part of mid tibia with a simple spur in front of a barbulate spur; apicoventral part of hind tibia with a simple spur in front of a large pectinate spur; petiole without a distinct anterior peduncle, with a triangular subpetiolar process anteroventrally; petiolar node in lateral view much longer than high; girdling constriction between abdominal segments III and IV distinct; abdominal sternite III with a distinct anteroventral flange beneath helcium; sting well developed.

Differentiation. The worker of this genus is easily distinguished from that of the other ponerine genera by its extraordinarily modified mandible and extremely developed eye.

Vietnamese species (1 sp.).

H. venator ( F. Smith, 1858) . Au (Ba Be, My Yen, Pu Mat, Hon Ba), Zry (Cat Tien).

Bionomics. Harpegnathos venator is rare in Vietnam. It probably occurs in forest edges and relatively sparse forests. We found an undergound nest along a dirt trail in a sparse forest.