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I found some caterpillars on my Damson. I don't know if they are doing any harm or just happened to be there but as there was more than one it is likely to be the former.

Dark brown/black with a yellow stripe down the back.

Any suggestions?

They are dead....so I hope you're not going to tell me it was a very rare species of butterfly but if you think it is please tell me before I wipe it out!

Anybody?

Haven't come across it on my damson trees, but if you feel like whiling away some time, theres a site here that could help you identify it:
http://www.whatsthatcaterpillar.co.uk/index.htm
Best of luck!

 :'( Thanks i know that site!