|Six-spot Burnet (Reg Fry)|
|Five-spot Burnet (Ian Rose)|
|Narrow-bordered Five-spot Burnet (David Howdon)|
The ground colour, degree of black spotting and colour of the hairs is said to be variable, which leaves no reliable way of telling Six- and Five-spot Burnet larvae apart, as far as I can tell. The NBFSB, though, has much longer hairs, as visible in the final pic.
Here are the two posted on the blog recently:
|Ian's larva from Pwll|
|Maggie's larva from Ffos Las|