black and scary dead beetle larva or aclypea opaca feeding on lettuce leaves

silphidae aclypea thickheads ancient historical fossil survivor eats leaves tender juicy larva black segments predator mollusk pest mollusceater hunter wildlife maggot biology color natural reproduction insects ecosystem small length summer green body damage dangerous decay destruction eat life scavenger winged maxillary arthropod carrion closeup crawl creature macro nicrophorus lettuce