Red pupae in my newly dug potatoes

[Greig]

Anyone know what this thing is? It starts to wriggle when left in the sunshine.

[Aberdeenplotter]

Its a castor, the pupa of a fly I think. Seen them on some of the fishing programmes

[ginger ninger]

It look like the pupae of the Angle Shade Moth. If it's about 15mm long I would put money on it. I have them all the time in the garden. There a beautiful moth, but there caterpillars do quite a bit of damage.

[Two_Sheds]

yeah, moth pupa, but apparently there are about 800 types that all look the same. You could try hatching it in a jar of soil