Mesostruma spinosa

This species, together with Mesostruma inornata and Mesostruma loweryi, have only been collected once. Only one species, Mesostruma eccentrica, is at all common in Western Australia, having been collected over 10 times. It is likely that additional species remain to be discovered in this part of Australia. The single known specimen of M. spinosa was collected from a pitfall trap.

Identification
Mesostruma spinosa can be separated from all other known species in this genus by the presence of distinct, elongate propodeal spines, the lack of broad propodeal lamellae and the narrower head (CI = 81, CI is greater than 88 in the other known species). There is little chance it will be confused with any other species.

Key to Mesostruma Species

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  spinosa. Mesostruma spinosa Shattuck, 2007: 51, figs. 9-12 (w.) AUSTRALIA.

Worker
Holotype. TL 2.9, HL 0.69, HW 0.56, CI 81, MandL 0.21, MandI 30, SL 0.41, SI 73, PW 0.40, ML 0.77. In dorsal view the anterolateral corners of pronotum rounded. Dorsum of mesosoma with scattered, shallow foveolate punctures spaced more than their width apart, the area between punctures smooth and lacking sculpturing. Propodeum armed with elongate spines, propodeal lamellae reduced to thin bands and essentially absent. Sculpturing on metapleural gland bulb consisting of indistinct rugae and punctures. Lateral surfaces of postpetiole rounded. First gastral segment immediately posterior of postpetiole smooth. Body colour yellow-red with light infuscation on dorsum of head above eyes, clypeus and first gastral tergite.

Type Material
Holotype worker from Western Australia, Manjimup (34°15'S 116°09'E), July, 1977 (J. D. Majer) (, No. 32-007281).