The only IDs I'll attempt are:
No. 3: Lipotriches sp.
No. 4: Yellow-spot bee (family Colletidae, Amphylaeus, Hylaeus or Meroglossa sp.) plus
Camera batteries are charged and I'll have another go when the weather fines up.
It's slightly less obvious why piophilids are called cheese-skippers. You need to see the maggots at work before the common name makes sense. When disturbed, they curl up, grabbing their ... ahem ...anal papillae with their mouthparts. And then they let go, springing several centimetres into the air. Boo!Jumping in dipteran larvae additionally occurs in several other, taxonomically diverse families. These include Tephritidae (fruit-flies), Cecidomyiidae (gall midges), Agromyzidae (leaf miner flies), Clusiidae (umm...?) and Phoridae (scuttle flies). (Phew, those are a few fly families that you don't come across very often! I wouldn't know a cecidomyiid from Adam!).