Strumigenys arrogantia

The modest number of collections are all from rainforest and wet forest habitat, with all the specimens found in litter samples.

Identification
Bolton (2000) - A member of the lyroessa complex in the Strumigenys lyroessa-group. Seven species in the lyroessa-complex have a pronotal humeral hair present: Strumigenys hostilis, Strumigenys dryas, Strumigenys liophila, Strumigenys micrura, Strumigenys imantodes, Strumigenys sydorata and arrogantia. The first of these is the only species in the group to have the first gastral tergite entirely sculptured. The second, dryas, has very dense standing pilosity and the third has long scapes and femora and a relatively long narrow head. The remaining four species are very closely related and share a characteristic reduced pilosity and set of dimensions. Two, micrura and imantodes, have a very reduced lamella on the propodeal declivity whilst in arrogantia and sydorata the lamella is broad and conspicuous. These last two form a close pair of siblings separated by details of mandibular structure, as given in their respective descriptions.

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

Nomenclature

 *  arrogantia. Strumigenys arrogantia Bolton, 2000: 868 (w.) BORNEO.

Worker
Holotype. TL 2.1, HL 0.64, HW 0.46, CI 72, ML 0.18, MI 28, SL 0.26, SI 57, PW 0.28, AL 0.60. Characters of lyroessa-complex. In profile preapical tooth of mandible about the same shape and size as the apicodorsal tooth. Dorsal margin of mandible, as seen in profile, not depressed distal of preapical tooth, the gap between preapical and apicodorsal teeth represented by a short transverse margin rather than a cleft. Upper scrobe margin with a row of anteriorly curved small spoon-shaped hairs. Apicoscrobal hair short, stiff and stout; dorsolateral margin of occipital lobe posterior to this with 5-6 similarly shaped but slightly shorter projecting hairs. Cephalic dorsum with standing hairs restricted to a stubbly transverse row along the occipital margin. Pronotal humeral hair short and stiff, pronotum otherwise without standing hairs. Mesonotum with 3 pairs of remiform to apically expanded short erect hairs, located along the dorsolateral margins. Width of lamella on propodeal declivity, at its broadest point below level of spiracle, more than half the length of the propodeal tooth. Erect hairs on first gastral tergite short and stiff, spatulate or expanded apically, distributed over the entire sclerite.

Paratypes. TL 2.1-2.2, HL 0.64-0.66, HW 0.49, CI 74-76, ML 0.18-0.20, MI 27-31, SL 0.26, SI 53-54, PW 0.28, AL 0.60 (2 measured).

Dimensions of non-paratypic workers. TL 2.0-2.2, HL 0.62-0.70, HW 0.47-0.51, CI 72-77, ML 0.18-0.22, MI 28-34, SL 0.24-0.29, SI 52-57, PW 0.28-0.31, AL 0.56-0.68 (10 measured).

Type Material
Holotype worker, Malaysia: Sarawak, Santubong, Kuching, v.1994 (Lobl & Burckhardt). Paratypes. 5 workers with same data as holotype (MHNG, ).

References based on Global Ant Biodiversity Informatics

 * Bolton, B. 2000. The Ant Tribe Dacetini. Memoirs of the American Entomological Institute 65
 * 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