Strumigenys alperti 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 : 639

Strumigenys alperti Fisher sp. n.

HOLOTYPE WORKER. TL 2.3, HL 0.60, HW 0.52, CI 87, ML 0.14, MI 23, SL 0.27, SI 52, PW 0.31, AL 0.64. Characters of yy / vai / u-complex. Lateral margin of clypeus, upper scrobe margin, and leading edge of scape each fringed with a row of curved spoonshaped hairs. Clypeal dorsum with short, anteriorly-directed spatulate hairs. Dorsum of head immediately behind clypeus with a transverse band of scale-like hairs, arranged in 3 - 4 rows, these hairs similar in size to those fringing the upper scrobe margins. Similar but somewhat more spoon-shaped hairs are also numerous on the dorsal surfaces of the occipital lobes, but they are absent from the median posterodorsal area of the head. There are no standing hairs of any description on the head, alitrunk, postpetiole or first gastral tergite. Eye conspicuous, with 4 - 5 ommatidia in the longest row. Promesonotal dorsum finely and densely reticulate-punctate, the sculpture fading posteriorly on the propodeal dorsum. Pleurae glassy smooth. Petiole node broader than long in dorsal view, finely reticulate-punctate and with several pairs of posteriorly curved decumbent spatulate hairs. Disc of postpetiole completely surrounded by spongiform tissue; disc with weak longitudinal striolate sculpture on each side of a smooth median strip. Basigastral costulae moderately developed, extending for some distance onto the first gastral tergite.

PARATYPE WORKERS. TL 2.4, HL 0.60 - 0.61, HW 0.52 - 0.54, CI 85 - 89, ML 0.14 - 0.15, MI 23 - 25, SL 0.27 - 0.28, SI 50 - 54, PW 0.31 - 0.32, AL 0.66 - 0.68 (2 measured). As holotype.

Holotype worker, Madagascar: 17 km. W Andapa, Res. d'Anjanaharibe Sud, 875 m., 2. xi. l 994, 14 O 45 ' 27.9 " S, 49 ° 30 ' 36.7 " E, primary rainforest, nest in log under moss, 543.12969 w (CD. Alpert) (MCZ).

Paratypes. 1 worker and 1 queen (dealate) with same data as holotype but 543.12968 q; 1 worker (gaster missing) with same data but 543.13484 w (MCZ, BMNH).

NON-PARATYPIC MATERIAL EXAMINED. Madagascar: 6.9 km. NE Ambanizana, 825 m. (B. L. Fisher); 9.2 km. WSW Befingotra, Res. Anjanaharibe-Sud, 1200 m. (B. L. Fisher); 6.5 km. SSW Befingotra, Res. Anjanaharibe-Sud 875 m. (B. L. Fisher).

The non-paratypic material shows greater size-variation than the type-series: HL 0.60 - 0.66, HW 0.51 - 0.58, CI 85 - 89, ML 0.15 - 0.17, MI 24 - 27, but otherwise matches all the critical diagnostic characters.

S. alperti is immediately separated from all other members of the group by its unique possession of a transverse band of scale-like hairs, made up of 4 - 5 rows, on the cephalic dorsum immediately behind the clypeus. S. alperti can be separated from carolinae by the presence of reticulate-punctate sculpture on the promesonotum. S. alperti and carolinae together can be separated from other two members of the sylvaini-complex by the following characters.

S. alperti + carolinae

1 Erect short simple hairs entirely absent from dorsal surfaces of head, alitrunk, waist segments and first gastral tergite.

2 Head dorsolaterally with broad scale-like hairs present. 3 Disc of postpetiole completely surrounded by spongiform tissue in dorsal view.

S. wardi + sylyaini

1 Erect short simple hairs present on dorsal surfaces of head, alitrunk, waist segments and first gastral tergite.

2 Head dorsolaterally without scale-like hairs.

3 Disc of postpetiole not surrounded by spongiform tissue in dorsal view, with anterolateral angles and anterior halves of sides free.