Strumigenys diasphax

The type material was collected from a mixed dipterocarp forest and at the edge of a primary montane forest.

Identification
Bolton (2000) - A member of the Strumigenys wallacei-group. Easily identified as this is the only species in the group to have standing hairs on the dorsolateral and occipital margins of the head and 4 pairs of erect stout hairs on the promesonotum. S. diasphax is smaller and more gracile than the other two species in the group and has a narrower head, CI 76-82 as opposed to CI 86-96 in Strumigenys gnathosphax and Strumigenys wallacei together.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Borneo, Indonesia, Malaysia.

Nomenclature

 *  diasphax. Strumigenys diasphax Bolton, 2000: 910 (w.) BORNEO.

Worker
Holotype. TL 2.3, HL 0.66, HW 0.54, CI 82, ML 0.36, MI 55, SL 0.44, SI 81, PW 0.29, AL 0.66. Apical fork of mandible with a minute intercalary denticle, inconspicuous and may be reduced to a tubercle (may be lost in some specimens). Scrobe in profile absent behind level of eye. Propodeum with short spines, declivity with a weakly spongiform lobe ventrally, the two connected by a weak carina. Ventral spongiform curtain of petiole at deepest distinctly greater than half the depth of the peduncle. Dorsal surface of head with narrowly spatulate ground-pilosity and 4 - 6 stout standing hairs along occipital margin. Appressed anteriorly curved hairs that fringe upper scrobe margin to level of eye minute, much smaller than hairs on leading edge of scape. Dorsolateral margin behind level of eye with 3-4 stiff stout projecting hairs that are directed more dorsally than laterally and are larger than the hairs on the leading edge of the scape. Pronotal humeral hair long, stout and stiff; dorsum of pronotum with a pair of standing hairs. Mesonotum with 3 pairs of erect stiff hairs that are expanded apically or remiform. Waist segments and first gastral tergite with stout stiff hairs that are simple or somewhat expanded apically, those on gaster suberect to erect. Mesopleuron mostly smooth but metapleuron and side of propodeum weakly reticulate-punctate, as is disc of postpetiole.

Paratypes. TL 2.2-2.3, HL 0.66-0.69, HW 0.52-0.55, CI 76-82, ML 0.36-0.38, MI 53-58, SL 0.40-0.44, SI 78-85, PW 0.28-0.30, AL 0.64-0.66 (7 measured).

Type Material
Holotype worker, Malaysia: Sarawak, 4th Div., Gn. Mulu N. P., v.-viii.1978, BM 1978-49, mixed dipterocarp forest (Hammond & Marshall). Paratypes. 12 workers, Malaysia: Sarawak, Gn. Penrissen, 1000 m., 23.v.1994, edge prim. montane for., #9a (Lobl & Burckhardt) (, BMNH, ).

References based on Global Ant Biodiversity Informatics

 * Hashimoto Y., Y. Morimoto, and M. Mohamed. 2002. Species list of ground and leaf litter ants collected in Lower Kinabatangan. Lower Kinabatangan : scientific expedition 2002/ 13-18.
 * Hashimoto Y., Y. Morimoto, and M. Mohamed. 2003. Species List of Ground and Leaf Litter Ants Collected in Lower Kinabatangan. Pp 13-18. In Lower Kinabatangan Scientific Expedition 2002, 176 pp. ISBN-13: 983-2369-11-8
 * Pfeiffer M.; Mezger, D.; Hosoishi, S.; Bakhtiar, E. Y.; Kohout, R. J. 2011. The Formicidae of Borneo (Insecta: Hymenoptera): a preliminary species list. Asian Myrmecology 4:9-58