Strumigenys ebbae

Identification
Bolton (2000) - A member of the ebbae complex in the Strumigenys koningsbergeri-group. The variation noted (see below) reflects the suspicion that more than one real species is currently concealed within the concept of ebbae. I have tentatively separated two closely related species from the mass, Strumigenys conturba and Strumigenys disturba, for the reasons given under those names, but can find no obviously stable characters to subdivide the mass further. Failure to resolve the variation is in large part due to shortage of material; a definitive analysis of this part of the ebbae-complex must await the amassing of more samples.

Within the ebbae-complex this small agglomeration of species (conturba, disturba, ebbae) is characterised by reduced concavity of the apical section of the inner mandibular margin, lack of a mandibular lamella, lack of a preocular impression and relative abundance of erect short hairs on the cephalic dorsum.

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

Nomenclature

 *  ebbae. Strumigenys ebbae Forel, 1905c: 11 (w.) INDONESIA (Java). See also: Bolton, 2000: 842.

Worker
TL 2.1-2.5, HL 0.57-0.69, HW 0.45-0.55, CI 76-80, ML 0.24-0.30, MI 40-46, SL 0.30-0.37, SI 66-72, PW 0.27-0.33, AL 0.58-0.72 (15 measured).

With characters of ebbae-complex. Preapical tooth short-conical and close to the apicodorsal tooth; length of preapical tooth half or less than half the width of the mandible at point where it arises. Inner margin of mandible proximal of preapical tooth straight to very shallowly convex, sharp-edged but without a lamella. Inner margin of mandible distal of preapical tooth only very shallowly concave, almost straight but weakly diverging from previous line of margin in some samples. Outer margin of mandible straight to very shallowly convex from base to level of preapical tooth. Upper scrobe margins evenly divergent, more or less straight from frontal lobes posteriorly; outer arc of eye visible in full-face view. Ventrolateral margin of head without a preocular impression although the margin may narrow fractionally immediately in front of the eye. Dorsum of head in profile with short erect hairs along occipital margin and numerous erect hairs anterior to this; with 1-3 pairs in front of pair at highest point of vertex, the anteriormost pair at about level of eye. Pronotum with two or more pairs of short standing hairs (as well as the humeral pair). Mesonotum with 1-3 pairs of short erect hairs. Propodeal dorsum often with a pair of erect hairs close to metanotal groove. Katepisternum partially to mostly smooth, metapleuron and side of propodeum superficially reticulate to densely reticulate-punctate, sometimes a small smooth patch on metapleuron. Bullae of femoral glands minute and inconspicuous on middle and hind legs, or invisible. Lamella on propodeal declivity narrow, its posterior (free) margin concave. Dorsum of petiole node reticulate-punctate. Disc of postpetiole with sculpture variable. In least sculptured samples disc smooth medially, finely punctulate posteriorly. In most strongly sculptured samples disc as strongly reticulate-punctate as petiole node and sometimes also with weak longitudinal rugulae on anterior portion of disc. Standing hairs on first gastral tergite simple or blunt apically.

Type Material
Holotype worker, INDONESIA: Java, Tjompea, leg. 11.iii.1904, ded. 6.vi.1904 (K. Kraepelin) [examined].