Comprehensive DescriptionRead full entry
Proatta Forel HNS , 1912
Worker monomorphic; head in full-face view elongate-pentagonal, with a shallow central longitudinal depression; preoccipital region forming four tubercles dorsally and a bilobate lobe laterally; frontal lobe very large and raised; frontal carina and antennal scrobe absent; median portion of clypeus protruded anteriad, in lateral view forming a steep anterior face; median clypeal seta absent; lateral portion of clypeus modified into a ridge or wall in front of antennal insertion; posteromedian portion of clypeus narrowly inserted between frontal lobes; antenna 12- segmented with indistinct 3-segmented club; eye small, convex well laterad; mandible triangular; masticatory margin with apical and two preapical teeth, followed by an inconspicuous tooth (4 teeth in total); promesonotum domed, with 3 pairs of tubercles dorsally, a tubercle anterolaterally, and a forked tubercle on posterior slope; promesonotal suture absent; metanotal groove well defined; a small tubercle present on dorsum of propodeum behind groove; propodeal spine long; propodeal lobe well developed as a round lamella; petiole with long peduncle and low node which has tubercles anterodorsally and posterodorsally; postpetiole short and high; gastral shoulder absent; standing hairs absent from dorsum of body (simple standing hairs present at apex of gaster and on mandible, slightly clavate hairs on second and third segments of gaster).
The worker of Proatta butteli HNS is easily separated from that of other known Vietnamese myrmicine genera by the tuberculate head and mesosoma.
Vietnamese species. The single described species in the genus is known from Vietnam: butteli Forel HNS (Nam Cat Tien, Phu Quoc).
Bionomics. Proatta butteli HNS is found in lowland forests of southern Vietnam, and nests under stones and wood fragments and in soil around tree bases. Adults are brick red and dull and are clad in dirt. When their nests are exposed, the cryptic workers freeze for a while, making them very difficult to detect.