Strumigenys norax Fisher, 2000

Bolton, B., 2000, The ant tribe Dacetini. With a revision of the Strumigenys species of the Malgasy Region by Brian L. Fisher, and a revision of the Austral epopostrumiform genera by Steven O. Shattuck., Memoirs of the American Entomological Institute 65, pp. 1-1028 : 666-667

Strumigenys norax Fisher sp. n.

HOLOTYPE WORKER. TL 3.0, HL 0.71, HW 0.55, CI 77, ML 0.41, MI 58, SL 0.50, SI 92, PW 0.33, AL 0.78. Characters of lysis-complex. Each mandible with 2 preapical teeth, situated in the apical third; proximal preapical tooth much longer than distal, the latter often reduced to small denticles. Upper scrobe margin without a projecting lamellate rim throughout its length; scrobe weakly marginate to rounded above vertical preocular groove on side of head. Eyes small, convex and plainly visible in full-face view; maximum diameter of eye subequal to maximum width of scape. Scape short, more or less straight, widest in the midsection; hairs on leading edge fine, slightly thickened apically. Cephalic dorsum densely clothed with short curved narrowly clavate ground-pilosity; upper scrobe margin fringed with hairs similar in size and shape as those on the dorsum. Cephalic dorsum with 6 stout standing hairs arranged in a transverse row close to the occipital margin; 3 (occasionally 2 or 4) pairs of stiff erect hairs on dorsolateral margin posteriorly, and 1 pair on vertex. Dorsum of head reticulate-punctate and often with superimposed rugulose sculpture on occipital angles. Pronotal humeral hair stiffly filiform and projecting; humeral angles rounded. Anterior margin of mesonotum with 2 pairs of stout filiform hairs: a pair on anterior margin and a more posteriorly situated pair. Propodeum with one pairs of short, fine, posteriorly curved hairs at anterior base of propodeal spines. Alitrunk dorsum with inconspicuous, short curved fine ground-pilosity. Dorsum of alitrunk in outline convex anteriorly, posterior alitrunk more or less flat to gradually sloping down to declivity. Metanotal groove not or minutely impressed. Anterior mesonotum without a minute carina above the mesothoracic spiracle. Propodeal spines narrowly triangular, almost spiniform; lamella absent from declivity. Pronotal dorsum and sides longitudinally striolate to costulate on a smooth surface, posterior pronotal disc striolate-punctate to rugulose punctate. Remainder of dorsal alitrunk striolate-punctate. Pleurae smooth and shiny with peripheral fine punctulate sculpture. Petiole node in dorsal view about as broad as long. Postpetiole disc longitudinally striolate on a finely punctulate surface. Spongiform appendages of petiole weakly developed; in profile ventral spongiform tissue of petiolar peduncle a narrow irregular strip along the base of the peduncle, depth of strip less than the width of the mandible blade when viewed in profile. Ventral spongiform lobe of postpetiole moderately developed. Basigastral costulae short and distinct. Dorsal surface of petiole with one pair of anteriorly projecting stout hairs; postpetiole and gaster with stout standing hairs which are slightly thickened apically. Colour light yellowish brown to medium brown.

PARATYPE WORKERS. TL 2.8 - 3.1, HL 0.68 - 0.72, HW 0.50 - 0.55, CI 74 - 77, ML 0.38 - 0.40, MI 56 - 58, SL 0.46 - 0.50, SI 86 - 94, PW 0.31 - 0.36, AL 0.71 - 0.80 (10 measured). As holotype.

Holotype worker, Madagascar: 9.2 km. WSW Befingotra, Res. Anjanaharibe-Sud, 14 ° 45 ' S, 49 C 28 ' E, 1200 Hi., 9. xi. 1994, sifted litter (leaf mold rotten wood), montane rainforest # 1192 (12) - 13 (B. L. Fisher) (MCZ). Paratypes. 11 workers and 3 queens (dealate) with same data as holotype but coded (l) - 5, (2) - 8, (3) - 10, (3) - 11, (4) - 4, (7) - 7, (9) - 10, (10) - 9, (23) - 10, (35) - 9, (42) - 5, (BMNH, SAM).

NON-PARATYPIC MATERIAL EXAMINED. Madagascar: Amboangy hill, 30 km. N Antalaha, 115 m. (CD. Alpert); 11.0 km. WSW Befingotra, Res. Anjanaharibe-Sud, 1565 m. (B. L. Fisher); 6.3 km. S Ambanizana, Andranobe, 25 m. (B. L. Fisher); 6.9 km. NE Ambanizana, 825 m. (B. L. Fisher); 2 km. W Andampibe, Cap Masoala, 125 m. (Alperl el al.); Fotodriana, Cap Masoala, 25 m. (Alpert et al.); 14 km. W Cap Est, Ambato, 100 m. (Alpert el al.); F. C. Sandranantitra 450 m. (H. J. Ratsirarson).

Measurements of this material extend the range shown by the type-series: HL 0.65 - 0.73, HW 0.47 - 0.53, CI 70 - 76, ML 0.38 - 0.41, MI 54 - 61, SL 0.45 - 0.49, SI 91 - 98 (7 measured).

S. norax and nambao are closely related and can be easily separated from other members of the rogeri-group by the following characters: left and right mandibles each with 2 preapical teeth; dorsolateral margin of head posteriorly with 2 - 4 stiff erect hairs that are longer than hairs on leading edge of scape; upper scrobe margin without a projecting lamellate rim above vertical preocular groove on side of head, scrobe weakly marginate to rounded. S. norax can be separated from nambao by the presence of two pairs of erect hairs on the mesonotum while nambao has only one pair of hairs.