I think it is part of an exoskeleton too, but there isn’t enough of it to identify. In all likelihood it is from  a harmless creature with a role to play in a healthy ecosystem. Diversity is a big predictor and a key component of a healthy yard. Selectively killing pests as they appear spares all the beneficial insects that feed birds, eat dead foliage,  maintain healthy soil, recycle nutrients, pollinate flowers and crops, and control pests.