[Lance Morgan]

If it is a mahogany colour it is likely angleshades which pupate just under the soil surface or in rubbish on the soil. Put it somewhere sheltered where mice or birds cannot get at it and it should be ok. Alternatively keep it in the house in a container with some sticks for it to climb and expand its wings. It should hatch very shortly and then you can release it. They are beautiful colour when they have just emerged.