Strumigenys milae 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 : 665

Strumigenys milae Fisher sp. n.

HOLOTYPE WORKER. TL 3.2, HL 0.73, HW 0.60, CI 83, ML 0.42, MI 57, SL 0.50, SI 82, PW 0.36, AL 0.77. Characters of Mam-complex. Each mandible with 2 preapical teeth, situated in the apical third; proximal preapical tooth longer than distal. Upper scrobe margin distinct, not bordered by a projecting laminar rim or flange throughout its length. Eyes moderate in size, convex and plainly visible in full-face view; maximum diameter of eye distinctly greater than maximum width of scape. Scape short, curved near base, widest in the midsection; hairs on leading edge fine, slightly flattened or spoon-shaped apically. Cephalic dorsum densely clothed with rows of curved narrow spatulate to spoon-shaped ground-pilosity; upper scrobe margin fringed with hairs which are the same size and shape as those on the dorsum. Cephalic dorsum with 4 stout standing hairs bordering occipital margin and a more anteriorly situated pair on vertex. Pronotal humeral hair absent; humeral angles rounded, posterolateral margin of pronotum bluntly marginate. Mesonotum with two pairs of stout filiform erect hairs; a pair on anterior margin and a shorter pair located posterior of mesonotal depression; one or two pairs of shorter hairs which curve toward the midline are present on anterior portion of mesonotum. Propodeum with one or two pairs of short, fine, posteriorly curved hairs at anterior base of propodeal spines or immediately anterior of propodeal spines. Ground-pilosity on alitrunk as on head, concentrated on the promesonotum. Dorsum of alitrunk in outline convex anteriorly, posterior mesonotum sharply depressed, posterior alitrunk more or less flat to gradually sloping to declivity. Propodeal spines narrowly triangular, spongiform, subtended by a narrow lamella on declivity. Alitrunk dorsum and sides of pronotum densely reticulatepunctate; pleurae smooth and shiny with peripheral punctures. Petiole node in dorsal view about as broad as long. Postpetiole reticulate-punctulate and with weak longitudinal striolate sculpture. In profile ventral spongiform tissue of petiolar peduncle an irregular, narrow strip along the base of the peduncle, its deepest point much less than maximum width of eye. Basigastral costulae short and distinct, with secondary and much longer superficial fine striolate sculpture arising between the shorter costulae. Dorsal surfaces of petiole, postpetiole and gaster with erect narrowly remiform hairs. Colour light to medium brown.

PARATYPE WORKERS. TL 2.9 - 3.1, HL 0.67 - 0.73, HW 0.54 - 0.58, CI 79 - 81, ML 0.38 - 0.41, MI 54 - 57, SL 0.46 - 0.48, SI 82 - 86, PW 0.33 - 0.37, AL 0.73 - 0.79 (3 measured). As holotype.

Holotype worker, Madagascar: Prov. Fianarantsoa, 28 km. SSW Ambositra, Ankazomivady, 20 ° 46.5 ' S, 47 ° 10.1 ' E, 1670 m., 14.1.1998, sifted litter (leaf mold, rotten wood), disturbed montane rainforest # 1625 - 4 (B. L. Fisher) (MCZ).

Paratypes. 1 worker with same data as holotype; 2 workers with same data as holotype but 1 l. i. 1998, # 1620 (2) - 2, # 1620 (5) - l (BMNH, SAM).

NON-PARATYPIC MATERIAL EXAMINED. Madagascar: Perinet & vie. (W. L. Brown).

Measurements of this material extend the range shown by the type-series: HL 0.71, HW 0.59, CI 83, ML 0.41, MI 59, SL 0.47, SI 81 (1 measured) but otherwise match diagnostic characters of the type-specimens.

S. milae is most similar to luca in the hilaris-complex. They both have relatively short scapes (SI <90). S. milae can be isolated from luca by the presence of two pairs of erect hairs on mesonotum, a shorter pair posterior to pair on anterior margin, the posterior portion of mesonotum sharply depressed behind the level of the anterior pair of hairs when viewed in profile. S. luca has a single pair of erect hairs on mesonotum. In addition, the petiole node of milae is evenly convex when viewed in profile while in luca , the petiole node is broadly triangular with a blunt apex. See hilaris for further discussion of the complex.