Crematogaster ebenina

Identification
Hosoishi (2015) - This species is unique among the Asian members of the Crematogaster ranavalonae-group in having a slender petiole. This species is similar to Crematogaster tumidula, but distinguished in having the petiole without anterolateral corners.

Distribution based on Regional Taxon Lists
Oriental Region: India, Myanmar. Palaearctic Region: China.

Nomenclature

 *  ebenina. Crematogaster (Oxygyne) ebenina Forel, 1902c: 199 (w.q.) INDIA. Senior synonym of corax:Hosoishi, 2015: 78.
 * corax. Crematogaster ebenina var. corax Forel, 1902c: 200 (w.) MYANMAR. Combination in C. (Oxygyne): Forel, 1903a: 683. Junior synonym of ebenina: Hosoishi, 2015: 78.

Worker
Hosoishi (2015) - (n = 4) HW 0.85-0.94; HL 0.81-0.86; CI 105-109; SL 0.69-0.76; SI 78-82; EL 0.18-0.19; PW 0.51-0.56; WL 0.98-1.05; PSL 0.11-0.13; PtL 0.24-0.26; PtW 0.24-0.27; PtH 0.16-0.17; PpL 0.14-0.16; PpW 0.24- 0.26; PtHI 64-67; PtWI 100-113; PpWI 162-173; WI 96-100.

Head appearing subquadratic in front view. Mandible weakly striate, with four teeth, apical and subapical teeth large, basal two teeth smaller. Scape exceeding posterior corner of head, with appressed setae, each of which is less than or as long as width of scape in length. Compound eye large and slightly projecting beyond lateral margin of head in full face view.

Ventrolateral katepisternal ridge indistinct. Propodeal spine long and stout; length equal to slightly greater than diameter of propodeal spiracle, directed upward, dorsum as high as anterior propodeum. Propodeal spiracle large and situated close to propodeal declivity in lateral view, directed posterolaterally.

In dorsal view, shape of petiole scoop with convex side, longer than broad. Anterolateral corner of petiole undeveloped, tapering anteriorly. Petiolar spiracle big, as large as half of propodeal spiracle in diameter. Postpetiole weakly bilobed but without longitudinal median sulcus. Petiole slightly wider than, or as wide as postpetiole in dorsal view. Integument essentially smooth and shiny. Clypeus generally smooth and shiny, but with feable rugulae. Malar region smooth and shiny without rugulae. Dorsal surface of promesonotum smooth and shiny. Lateral surface of pronotum smooth and shiny. Mesopleuron and lateral propodeum generally shiny, but with feable rugulae. Dorsal surface of propodeum smooth and shiny.

Erect pilosity almost absent. Dorsum of head, clypeus and mesosoma with short and appressed sparse setae. Clypeus without longer setae on anteriormost portion. Anterior clypeal margin with one single longer setae and two pairs of longer setae, mixed with some shorter setae on the side. No erect setae on pronotal shoulder. Posterolateral tubercle with some decumbent to appressed shorter setae. Ventral surface of petiole with appressed setae. Postpetiole with some shorter setae posteriorly. Fourth abdominal tergite with appressed setae.

Body color reddish brown.