Crematogaster imperfecta

Identification
This species is very similar to Crematogaster hashimi, but differs in having elliptical propodeal spiracles and a slender petiole.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Malaysia.

Nomenclature

 *  imperfecta. Crematogaster imperfecta Hosoishi, 2015: 82, fig. 32 (w.) MALAYSIA.

Worker
(type workers, n = 6). HW 0.77-0.87; HL 0.72-0.81; CI 103-108; SL 0.63-0.71; SI 78-83; EL 0.16-0.18; PW 0.48-0.54; WL 0.86-0.95; PSL 0.02-0.04; PtL 0.24-0.26; PtW 0.21-0.23; PtH 0.13-0.15; PpL 0.14-0.16; PpW 0.22-0.26; PtHI 54-60; PtWI 88-92; PpWI 156-167; WI 104-114.

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 width of scape in length. Compound eye large and slightly projecting beyond lateral margin of head in full face view.

Ventrolateral katepisternal ridge indistinct posteriorly. Propodeal spine undeveloped, but as small tubercule in some workers; length distinctly shorter than propodeal spiracle. Propodeal spiracle large, situated close to the propodeal declivity in lateral view, directed laterally.

In dorsal view, shape of petiole scoop with convex side, longer than broad. Anterolateral corner of petiole developed. Petiolar spiracle small, less than half of propodeal spiracle in size. In dorsal view, postpetiole slightly broader than long. Postpetiole weakly bilobed, but without longitudinal median sulcus. Postpetiole as wide as petiole in dorsal view.

Integument essentially smooth and shiny. Clypeus smooth and shiny without rugulae. Malar region smooth and shiny. Dorsal surface of promesonotum smooth and shiny. Lateral surface of pronotum smooth and shiny. Mesopleuron smooth and shiny. Dorsal surface of propodeum smooth and shiny. Lateral propodeum smooth and shiny.

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

Body color reddish brown.

Etymology
The specific name refers to the undeveloped propodeal spines.