Bembix rostrata (L.) (Hymenoptera, Crabronidae) de retour en Wallonie (Belgique)

Abstract

Bembix rostrata (L.) (Hymenoptera, Crabronidae) back in Wallonia (Belgium).

Asymmetrical gene flow between coastal and inland dunes in a threatened digger wasp

“…Especially for the connections from coastal France to inland (Fig. 6), intermediate populations might be present (Bitsch et al 1997;Barbier 2007). Therefore, the detected connections between coastal France and inland regions might not be from directly dispersing individuals, but through an indirect connection of an unsampled French population.…”

“…Large herbivores have been introduced in many coastal dune reserves during the last three decades to revitalize dune dynamics (Provoost et al 2004), but might have mixed effects on local arthropod species due to intense trampling (Bonte and Maes 2008;van Klink et al 2015;Batsleer et al 2022b). Second and contrastingly, inland sandy soils in Flanders are acidic (Decleer 2007) (Blösch 2000;Jacobs 2000;Klein and Lefeber 2004;Barbier 2007;Bogusch et al 2021). In Belgium and the Netherlands, mostly inland populations were lost, resulting in a distribution with local strongholds at the coast and more fragmented or isolated populations present inland (Klein and Lefeber 2004).…”

Asymmetrical gene flow between coastal and inland dunes in a threatened digger wasp

“…We used the following criterion to specify newly established populations: Flemish populations were indicated as new populations if no observations were known in a radius of 2.5km from before 16-10-2017 (reported before the summer of first sampling on the citizen-science species observation platform www.observations.be). French and Walloon populations were known to be historically present from literature (Barbier 2007). The individuals from the new populations were added to the assignments test, to deduce the possible source of these putative new populations.…”