As I was cropping this shot of a Common Carder Bumblebee - Bombus pascuorum - I spotted something that led to the above question. So how many species can you see in this shot? Answer at the bottom of the page (don't cheat!). Helpful hint: all the leaves belong to the flower.
Greater Stitchwort - Stellaria holostea - sneaks up stealthily due to the fact that the leaves look like grass:
Common Dog Violet - Viola riviniana - is about two weeks later than usual this year.
I counted 4 species:-
Carder Bumble Bee.
Puccinia ranunculi (fungal rust on leaf)
A parasitic bug on the bee (shown below).