Nomada sexfasciata Panzer, 1799

Gérard, Maxence, Fiordaliso, William, Ferrais, Louise, Fournier, Chloé, Hairault, Malo, Lheureux, Lise, Rosa, Paolo & Ghisbain, Guillaume, 2025, Wild bee diversity of the National Park of the Semois Valley (Belgium), Biodiversity Data Journal 13, pp. e 144223-e 144223 : e144223-

Nomada sexfasciata Panzer, 1799

Conservation status

CR

Distribution

Recent records of N. sexfasciata in Belgium are largely restricted to the Fagne-Famenne geological region and the south-eastern part of the Campine. Its populations have declined by more than 80 % between 1900–1969 and 1970–2017, particularly around Brussels and in the Province of Liège ( Drossart 2019). However, this species has always been rare and habitat degradation - especially the loss of Fabaceae - rich grasslands, which support its host species - is likely the main threat to its continued survival.

Notes

Nomada sexfasciata is a brood parasite of two threatened species in Belgium, both sampled during our inventory: Eucera longicornis and E. nigrescens ( Westrich 2008) . It shares the same habitats as its hosts, primarily grasslands rich in Fabaceae species.

Diagnosis

This species of Nomada is relatively large, measuring between 12 and 14 mm in length (Fig. 11 ). The metasoma is entirely black, with prominent yellow lateral patches on the first three tergites. The mesosoma is notably hairy for a Nomada species and bears two yellow spots on the scutellum. A distinctive characteristic of this species, compared to other species from Belgium, is its particularly inflated clypeus (seen from the side), and relatively wide malar gap between the eyes and the base of the mandible ( Smit 2018, Falk and Lewington 2019).

Figures

Figure 11. Nomada sexfasciata, ♀. Habitus in lateral view and head in oblique view. Scale bar: 5 mm. Photo credit: Paolo Rosa.