Myrmicaria Saunders ^HNS, 1842

The genus Myrmicaria ^HNS is assigned to the tribe Myrmicariini ^HNS (Bolton 2003). Workers of Vietnamese species have the following features.

Worker monomorphic; head in full-face view oval or subrectangular with round posterior corners and straight posterior margin; frontal lobe in full-face view relatively large, completely concealing torulus; frontal carina indistinct or absent; antennal scrobe absent; median portion of clypeus with roundly convex anterior margin; posteromedian portion of clypeus broadly inserted between frontal lobe; median clypeal seta absent; mandible relatively narrow, with 4 teeth; antenna 7-segmented, gradually incrassate or with indistinct 3-segmented club; eye large and strongly convex laterad, located behind midlength of side of head in full-face view and relatively high on side in lateral view; mesosoma in lateral view short and high; promesonotum in lateral view a little higher than anterodorsal border of propodeum; promesonotal suture a weak or faint dorsal impression; anteroventral corner of promesonotum forming an acute angle or spine; metanotal groove weakly impressed; posterior slope of promesonotum and dorsum of propodeum margined laterally with a carina that connects with a well-developed propodeal spine; propodeal lobe absent; legs slender and long; petiole with long anterior peduncle and well-developed node; subpetiolar process absent; postpetiole in lateral view relatively long; gastral shoulder present; sting well developed.

The worker of Myrmicaria ^HNS is easily separated from those of other Vietnamese myrmicine genera by 7-segmented antennal segments, short and high mesosoma, and elongate petiolar peduncle.

Vietnamese species. Two species have been recognized by us from Vietnam: brunnea Saunders ^HNS [sp. eg-1] (Bac Can, Ba Vi, Cuc Phuong) and vidua F. Smith ^HNS [sp. eg-2] (Da Lat, Que Phong, Nui Chua, Pu Mat, Van Ban).

Bionomics. Myrmicaria brunnea ^HNS and M. vidua ^HNS inhabit various habitats such as fruit gardens, sparse forests, forest edges and well-developed forests, and nest in soil, often building big mounds with soil particles. Workers scavenge dead animals and also tend homopterans.