Species of the meridionalis group

The meridionalis group contains the following three species: Sphex meridionalis, S. nefrens sp. nov. and S. occidentalis sp. nov.

Members are characterized through their black, more or less perpendicularly-oriented erect propodeal setae which are slightly curved towards the anterior (Figs 3–4), and therefore closely resemble some species of the umtalicus group. Nonetheless, several characters unequivocally separate the two groups. Firstly, females of the meridionalis group (Fig. 8) lack the coarse scutellar vestiture present in those of the umtalicus group (Figs 3–4). As this can be difficult to assess without practice, a useful indicator is the presence or absence of long erect setae, of similar quality to those on the metanotum, near the scutellar center. Females of the meridionalis group only have long erect scutellar setae near the posterolateral margin of the scutellum, whereas those of the umtalicus group usually also have some near the center. Secondly, male specimens of the umtalicus group always have a conspicuous tooth-like process that emerges from below the free clypeal margin (Fig. 27). This structure is absent in members of the meridionalis group.