Is this Spidermite or something else ?

I have grown Achillea this year from seed - they were growing well - now, just as they have flower buds forming the top leaves are looking twisted. I sprayed with SBPI last week (although I didnt see any bugs at the time) which improved the new growth somewhat - but today noticed this -



You can see the damage they have caused - looks like a youngster on the right - although the stripey one is visible to the eye so maybe too big to be a spidermite - but what then ? some sort of aphid ? not seen them before - either way they got squirted again and moved away from other plants for the moment.

S

 

Many thanks Armandii - put my mind at rest -are they all red ? I thought you can get other colour spidermites - had two-spot ones on a rubber plant once I had under lights which were yellow/green with black markings although only spottable through magnifying glass.

Aphids though, I can manage

S