Comprehensive DescriptionRead full entry
Vollenhovia Mayr HNS , 1865
Worker monomorphic; head in full-face view subrectangular; frontal carina and antennal scrobe absent; median portion of clypeus raised, laterally margined with a slight to conspicuous longitudinal carina; anteromedian portion often forming a transverse strip; an isolated median seta absent; posteromedian portion relatively narrowly inserted between frontal lobes; lateral portion of clypeus never modified into a distinct ridge or wall in front of antennal insertion; mandible triangular; masticatory margin with 6 or more teeth; antennae 11- or 12-segmented, with 3-segmented club; eye always present, small to medium sized; mesosoma in lateral view long and low; promesonotum in lateral view usually not domed; promesonotal suture absent dorsally; metanotal groove weakly to slightly impressed dorsally; posterodorsal portion of propodeum with rounded corners or small teeth; propodeal lobe present as carina or low lamella; petiole nodiform; anterior peduncle short and obscure; posterodorsal margin of petiole produced posterodorsad as a rim which is distinctly (or at least a little) higher than the dorsal outline of helcium of petiole when waist segments stretched posteriad; subpetiolar process usually (but not always) developed as a large lamella; gastral shoulder absent.
The worker of Vollenhovia HNS is easily separated from those of other known Vietnamese myrmicine genera by the flattened body and the posterodorsal margin of petiole produced as a rim.
Vietnamese species. Seven species have been recognized by us from Vietnam: sp. eg-1 [= sp. 40 and sp. 54 of SKY: Eguchi et al., 2005] (Cuc Phuong, Sa Pa, Tam Dao, Tay Yen Tu); sp. eg-2 [= sp. 34 of SKY: Eguchi et al., 2005] (Ba Vi, Chua Yen Tu, Sa Pa, Pu Mat, Tam Dao, Tay Yen Tu, Van Ban); sp. eg-5 [= sp. 36 of SKY: Eguchi et al., 2005] (Ba Vi); sp. eg-6 (Chua Yen Tu); sp. eg-7 [= sp. 39 of SKY: Eguchi et al., 2005] (Ba Vi, Chua Yen Tu, Cuc Phuong, Tam Dao, Tay Yen Tu); sp. eg-8 (Pu Mat, Nam Cat Tien); sp. eg-9 (Nam Cat Tien).
Bionomics. Vollenhovia HNS species usually inhabit forest habitats and nest in rotting twigs, wood fragments and logs, and in spaces under the bark of logs.