With its bristly body, brown-tinged wings, black femora, and red/brown tibia and tarsi, I think this may be the dagger fly Empis tessellata, but these are tricky flies to identify so don’t take my word on that.

And, to be honest, I’m not too concerned about identifying the exact species because what fascinates me more is their mating behaviour, which I was fortunate to witness during Sunday’s walk. According to the Naturespot website

Though it feeds on nectar it is also a predator and catches other insects using its long pointed proboscis to pierce their bodies. Males of Empis opaca and E. tessellata present a ‘gift’ to the female, in the form of a dead insect, before mating takes place. Females will not mate with males who do not present a gift.