Bolton, B., 2000:
HOLOTYPE WORKER. TL 2.9, HL 0.70, HW 0.65, CI 93, ML 0.31, MI 44, SL 0.37, SI 57, PW 0.38, AL 0.77. Characters of abdera-complex. Mandible with 2 preapical teeth, the distal smaller than the proximal. A small denticle is present at base of apicoventral tooth of fork. Hairs on the dorsum of head posterior of frontal lobes and along upper scrobe margin are not similar in shape to hairs on leading edge of scape. Hairs along upper scrobe margin short, simple and appressed. In profile, promespnotal dorsum convex; propodeal dorsum convex anteriorly, sloping posteriorly to the declivity. Ground-pilosity of dorsum of head posterior to frontal lobes and promesonotum consisting of numerous small scale-like to orbicular hairs, most of which are closely applied to the surface. Erect, short and narrowly clavate hairs present on head and alitrunk as follows: a transverse row of 4 across the cephalic dorsum close to the occipital margin, one pair on the mesonotum. Hairs on petiole, postpetiole and gaster filiform to clavate. postpetiole disc with fine dense reticulate-punctate to reticulate-granulate sculpture. In profile, ventral spongiform lamella of petiole not well developed, tapering to a narrow strip near peduncle base. Propodeal tooth a blunt triangle that is incorporated in the lamella, the latter a narrow strip.
PARATYPE WORKER. TL 2.8 - 3.0, HL 0.70 - 0.71, HW 0.65 - 0.68, CI 93 - 96, ML 0.29 - 0.31, MI 42 - 44, SL 0.36 - 0.38, SI 54 - 56, PW 0.37 - 0.40, AL 0.69 - 0.72 (4 measured). As holotype.
Holotype worker, Madagascar: 40 km. S Ambalavao, Res. Andringitra 22 Ã‚Â° 13 ' S, 46 Ã‚Â° 58 ' E, 1275 m., 15. x. 1993, sifted litter (leaf mold, rotten wood), montane rainforest, # 793 (47) - 6 (B. L. Fisher) (MCZ). Paratypes. 4 workers with same data as holotype but coded (49) - 6, (23) - 8 (BMNH, SAM).
NON-PARATYPIC MATERIAL EXAMINED. Madagascar: 29 km. SSW Ambositra, Ankazomivady 1700 m. (B. L. Fisher).
Measurements of non-paratypic material extends the range shown by the type-series: HL 0.63 - 0.67, HW 0.58 - 0.64, CI 90 - 96, ML 0.27 - 0.30, MI 43 - 46, SL 0.34 - 0.39, SI 57 - 61 (4 measured).
S. abdera is easily distinguished from other species in the arnoldi-group by the presence of 2 preapical teeth and the absence of curved spatulate to spoon-shaped hairs on the dorsal surfaces of the head, alitrunk and petiole.