Pyramica Roger

Eguchi, K., Viet, B. T. & Yamane, S., 2011, Generic synopsis of the Formicidae of Vietnam (Insecta: Hymenoptera), Part I - Myrmicinae and Pseudomyrmicinae., Zootaxa 2878, pp. 1-61 : 26-27

Pyramica Roger , 1862

Taxonomy. Pyramica was synonymized with Strumigenys by Roger (1863), but it was revived and revised by Bolton(1999 and 2000), and assigned to the tribe Dacetini . We follow Bolton 's concept of the genus (but see also Baroni Urbani & De Andrade 2007). Workers of Vietnamese species have the following features. Species belonging to the argiola- and murphyi-groups of Pyramica are characterized by linear mandibles, like those in Strumigenys , but representatives of these groups have not yet been found from Vietnam.

Worker monomorphic; head in full-face view elongate-triangular or elongate-cordiform; frontal lobe horizontal, covering antennal insertion; frontal carina distinct; antennal scrobe usually distinct but sometimes weak; median portion of clypeus expanded well anteriad; posteromedian part of clypeus broadly inserted between frontal lobes; mandible usually elongate-triangular, with serially dentate masticatory margin; labrum with a pair of large distal lobes which arise from across entire width of labrum; antenna 4- or 6-segmented, with two apical elongate segments forming a club; eye small to medium, located ventrolaterally below antennal scrobe; promesonotum often raised; promesonotal suture absent dorsally; metanotal groove usually impressed weakly or absent, but rarely remarkably stringly impressed; propodeal spine present or absent; posterior slope of propodeum often marginate laterally with lamelliform appendage; propodeal spiracle located high on side of propodeum and very close to, or at the posterior margin of the side; forecoxa basally with a rim or carina; petiole pedunculate, with low node; postpetiole with broad elliptical dorsal mound; spongiform appendages usually (but not always) well developed ventrally and laterally on both petiole and postpetiole.

The worker of Pyramica is similar to that of Strumigenys . In all Pyramica species so far known from Vietnam the mandible is elongate-triangular with a serially dentate masticatory margin, and so they are easily distinguished from Strumigenys species. However, for precise identification, the morphology of labrum needs to be examined.

Vietnamese species. Eight species has been recognized by us from Vietnam: canina (Brown & Boisvert) [= sp. eg-2] (Tay Yen Tu); dohertyi (Emery) [= sp. eg-1] (Ba Vi, Sa Pa, Tay Yen Tu, Tam Dao, Van Ban); kichijo (Terayama, Lin et Wu) [= sp. eg-5] (Cuc Phuong); japonica (Ito) [= sp. eg-6] (Sa Pa); mitis Brown [= sp. eg-3] (Ba Vi, Cuc Phuong, Nam Cat Tien); nepalensis (De Andrade) [= sp. eg-4] (Ba Be); sp. eg-7 (My Yen, Van Ban); sp. eg-8 (Nam Cat Tien).

Bionomics. The majority of species of Pyramica are litter dwellers in well-developed forest. Nests are often found in and under rotting twigs and wood fragments on the forest floor. Because we have not yet employed Winkler bags, used to extract small soil animals from litter, our collection of Pyramica species may be under-represented.