Messor platyceras

Distribution based on Regional Taxon Lists
Palaearctic Region: Iran.

Nomenclature

 *  platyceras. Messor platyceras Crawley, 1920a: 163, pl. 5, fig. 3 (s.w.) IRAN.
 * Subspecies of clivorum: Emery, 1921b: 210.
 * Subspecies of structor: Bolton, 1995b: 256.
 * Status as species: Khalili-Moghadam et al., 2019: 173.

Taxonomic Notes
Khalili-Moghadam et al. (2019) - Based solely on the original description, EMERY (1921) placed Messor platyceras CRAWLEY, 1920 as a subspecies of Messor structor (LATREILLE, 1798). This point of view was accepted by BOLTON (1995). In their revision of the Messor structor group, STEINER et al. (2018) commented regarding M. platyceras and its variety that both taxa “do not fit morphologically either of the two species occurring closest to Iran, M. muticus and Lineage 7.” and concluded that both of CRAWLEY's taxa were “not relevant to identifying names for any of the species characterized here”. The location of the types is unknown, but CRAWLEY (1920) well characterized M. platyceras by the following combination of characters: first segment of funiculus longer than 2nd, flattened so as to be twice as long as broad with parallel sides, and much wider than 2nd segment when viewed on its flat side (Figs 8, 9), strong body sculpture (Figs 3-6), and base of gaster longitudinally striate for a short distance, the rest smooth and shining (Fig. 7). This combination of characters is unique within the Messor structor group, especially the distinctly striate base of the gaster in combination with the elongate and flattened first segment of the funiculus. This set of characters was observed in several of the samples noted above, and we concluded that they belong to this forgotten taxon. The location of the types of M. platyceras is unknown, but the type locality (NW Iran) and the unique set of characters led us to infer that Messor platyceras is a good species from the Messor structor group. The samples examined indicated that there were workers in a single nest with an almost completely black body and with a partly reddish mesosoma. We therefore concluded that Messor platyceras var. rubella was only an infraspecific colour variation.