Crematogaster overbecki Viehmeyer

Hosoishi, Shingo & Ogata, Kazuo, 2012, Revision of the Crematogaster brevis complex in Asia (Hymenoptera: Formicidae), Zootaxa 3349, pp. 18-30 : 24-25

Crematogaster overbecki Viehmeyer

( Figs 2 a, 4b, 9)

Crematogaster overbecki Viehmeyer, 1916: 123 , fig. 3.

Syntype worker from SINGAPORE (H. Overbeck). ( NHMB) [examined] .

Combination in C. ( Orthocrema ) by Emery, 1922: 132; in C. ( Mesocrema ) by Santschi, 1928: 33.

Measurements and indices. HW 0.63; HL 0.63; CI 100; SL 0.44; SI 70; EL 0.12; PW 0.4; WL 0.64; PSL 0.11; PtL 0.18; PtW 0.19; PtH 0.13; PpL 0.12; PpW 0.18; PtHI 72; PtWI 106; PpWI 150; WI 95 (One syntype worker measured).

General description of worker. Compound eyes slightly projecting from lateral margin of head. Scape reaching posterior corner of head, the scape with standing and appressed setae.

Pronotal shoulders developed as ridges. Mesonotal dorsum highly convex in lateral view. Metanotal groove concave. Propodeal spines longer than the diameter of propodeal spiracles, curved upward. Anterior margin of metapleural gland bulla not reaching anterior margin of propodeal spiracle.

Petiole in dorsal view rectangular with angular corners. Subpetiolar process weakly developed, angulate. Postpetiole bilobed behind, but without distinct longitudinal median sulcus.

Dorsal surface of head generally smooth, but the malar region with longitudinal rugulae. Clypeus with two distinct pairs of rugulae laterally. The rugulae connecting the anterior and posteror clypeal margins. Dorsal face of promesonotum with relatively open, reticulate sculpture with shiny interspaces. Lateral surface of pronotum generally smooth and shining, but some longitudinal rugulae extending from the anterior portion of pronotum.

Mesopleuron smooth, but lower portion of mesopleuron weakly sculptured. Longitudinal rugulae developed on the front and behind the metanotal groove in lateral view. Some rugulae on the mesonotum extending to the anterior portion of propodeal dorsum.

Fourth abdominal tergite with abundant appressed setae, and sparse standing setae.

Distribution. This species is known only from the type locality in Singapore.

Remarks. This species is similar to C. brevis , but can be distinguished by lacking median rugula on the clypeus, and by the distinctive sculpture of the mesonotal dorsum.

Figures

FIGURES 1 – 3. 1. Full face view of head. 1 a, Crematogaster treubi; 1 b, C. (Orthocrema) longipilosa. Arrow indicates anterolateral margin of clypeus. Scale bars are all 0.5 mm. 2. Occipital carina in posterior view. 2 a, Crematogaster overbecki; 2 b, C. bouvardi. Arrow indicates occipital carina. Scale bars are all 0.5 mm. 3. Petiole and postpetiole in dorsal view. 3 a, Crematogaster brevis; 3 b, C. treubi; 3 c, C. walshi. Scale bars are all 0.5 mm.