bug 'shell'??

bug 'shell'??

Observation - bug 'shell'?? - Global. Description: small hard case feels a bit like hard cardboard, not quite wooden. Found as one of many (maybe 20??) near to compost bin in my garden. All have exact same small hole in them. Suggests something has hatched out of it, I'm wondering what? May have been in c

small hard case feels a bit like hard cardboard, not quite wooden. Found as one of many (maybe 20??) near to compost bin in my garden. All have exact same small hole in them. Suggests something has hatched out of it, I'm wondering what? May have been in compost as found when emptying.