Strumigenys sylvaini 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 : 644-645

Strumigenys sylvaini Fisher sp. n. (Fig. 388)

HOLOTYPE WORKER TL 2.0, HL 0.65, HW 0.56, CI 87, ML 0.19, MI 30, SL 0.30, SI 54, PW 0.38, AL 0.71. Characters of sylvaini-complex. Entirety of head blanketed with fine, dense reticulate-punctate sculpture, opaque everywhere. Dorsum of head without scale-like hairs that are similar in size to those on the fringing rows. Instead the head dorsally with sparse, minute and inconspicuous decumbent to appressed spatulate hairs, and with a row of 4 short erect hairs close to the occipital margin. Eye with 4 - 5 ommatidia in the longest row. Dorsal alitrunk, petiole node, and postpetiole disc finely reticulatepunctate, the postpetiole disc with feeble longitudinal rugulae. Pleurae smooth and shining. Short standing hairs present as follows: mesonotum with a single pair, 1 pair posterodorsally on the petiole node, 2 pairs posterodorsally on the postpetiole, transverse rows of hairs present between a basal and an apical row on the first gastral tergite. Lamella of propodeum narrow below the triangular propodeal spines, leaving most of the spine length free. Petiole node in dorsal view broader than long. Disc of postpetiole in dorsal view not completely surrounded by spongiform tissue, the anterolateral angles and anterior halves of the sides free. Basigastral costulae short but well developed and conspicuous.

PARATYPE WORKERS TL 1.6 - 2.0, HL 0.60 - 0.65, HW 0.55 - 0.56, CI 86 - 91, ML 0.18 - 0.19, MI 29 - 30, SL 0.28 - 0.29, SI 51 - 53, PW 0.34 - 0.37, AL 0.67 - 72 (4 measured) As with holotype.

Holotype worker, Madagascar: 38 km. S Ambalavao, Res. Andringitra 22 ° 12 ' S, 46 ° 58 ' E, 1680 m., 24. x. 1993, ex root mat, montane rainforest # 827 - 2 (B. L. Fisher) (MCZ).

Paratypes. 1 worker and 1 queen (dealate) with same data as holotype; 3 workers with same data as holotype but 23. x. 1993 # 830 (50) - 3, # 830 (36) - 8, and # 830 (40) - 5 (BMNH, SAM).

NON-PARATYPIC MATERIAL EXAMINED. Madagascar: R. S. Manongarivo, 17.3 km. 218 ° SW Antanambao 1580 m. (B. L. Fisher); R. S. Manongarivo, 20.4 km. 219 ° SW Antanambao 1860 m. (B. L. Fisher); 9.2 km. WSW Befingotra, Ris. Anjanaharibe-Sud 1280 m. (B. L. Fisher); Andranobi, Route d'Andriamena, ca 25 km. W Morarano Sud ca 1250 m. (A. Peyrieras); For. d'Ambatofitorahana 293 to 294 km. on route national no. 7 1800 m. (A. Peyrieras); Itremo Mts. 1680 m. (A. Peyrieras); 28 km. SSW Ambositra 1660 m. (P. S. Wtrd); 29 km. SSW Ambositra, Ankazomivady 1700 m. (B. L. Fisher); 40 km. S Ambalavao, Ris. Andringitra 1275 m. (B. L. Fisher); 8.0 km. NE Ivohibe 1200 m. (5. Razafimandimby); 9.0 km. NE Ivohibe 900 m. (S. Razafimandimby); R. S. Ivohibe, 7.5 km. ENE Ivohibe 900 m. (S. Razafimandimby); R. S. Ivohibe 8.0 km. E Ivohibe 1200 m. (S. Razafimandimby); R. S. Ivohibe, 6.5 km. ESE Ivohibe 1575 m. (S. Razafimandimby); 13 km. NW Enakara, Ris. Andohahela 1250 m. (B. L. Fisher); Mandena, 8.4 km. NNE 30 ° Tolagnaro 20 m. (B. L. Fisher).

Measurements of this material extends the range shown by the type-series: HL 0.59 - 0.67, HW 0.52 - 0.57, CI 85 - 88, ML 0.18 - 0.19, MI 28 - 31.

One of the most widely distributed member of the dexis-group in the rainforest region of Madagascar. Distinguished from other members of the sylvaini-complex by having:

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

2 Postpetiole disc reticulate-punctate with feeble longitudinal rugulae.

3 First gastral tergite with standing hairs present between the apical and basal rows.