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I saw these flies on a hedge (probably Prunus lusitanica) in the utmost South of the Netherlands in April 2022.
Can someone tell me with species or genus this is? Thank you.

Best regards,
Annemiek van Dijk

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Another image of these flies

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Chloropidae. Thaumatomyia?

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Thank you Jan Maca. It seems to have the flat-topped scutellum. I did not recognize it because of the rear appendices but I have learned now that those are pheromone sacks, so this would be a male Thaumatomyia (maybe T. notata?)

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Chloropidae: Thaumatomyia spec. is correct. Not all Thaumatomyia species possess those peculiar eversible testicle-like odor sacs (= vesicles), e.g. T. trifasciata, rufa and hallandica males lack them. Boppré & Pitkin (1988, Entomologia generalis 13(1-2): 81-85), Steyskal (1945, Bull. Brooklyn ent. Soc. 40(2): 48), and Kotrba (2006, Europ. J. Ent. 106(1): 57-62) wrote about attractions, repellents, odors, pheromones, display, fight, wing waving, copulation and alcaloids in connection with Thaumatomyia. It is well known that the huge overwintering swarms of Th. notata in buildings and hollow old trees let behind smelling bio-chemicals which attract one or more autumns later again new masses of those flies. Thaumatomyia [ancient Greek] means "noteworthy fly", notata [Latin] means "should be noted", too. Meigen (1930) selected a well agreeing name and he knew the aggregation phenomenon. I collected 278 articles and notes published about it during now 190 years [see database].

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Thank you Herr von Tschirnhaus for the interesting additional information and literature links for Thaumatomyia biology.
Thaumatomyia notata is worth noting, both for other diptera and for entomologists!

Best regards,Annemiek van Dijk