Possibly Cerceris rybyensis??

[beeflysmith]

I think the first photo is of Cerceris rybyensis by comparison with photos on
Cerceris rybyensis (Linnaeus) (Ornate Tailed Digger Wasp) but then the 2nd and 3rd photo - although taken only a couple of minutes later on the same shrub they (photos 2 & 3) are maybe a different insect but MAY be the same species.
The 4th photo was taken at the same location a couple of weeks later (31/7/2010) could anyone tell me if this is also a Cerceris rybyensis (I didn't even realise until I put the photo on the computer that it has captured a small bee, common prey of Cerceris rybyensis I think).
Is there much difference in the markings between individuals or male/female?
Thanks in advance
Nick

[eucera]

All pics of Cerceris rybyensis

[beeflysmith]

Thanks for that, I've posted it on 3 different sites and not one answer from any other than this one, cheers
Nick