This is an American silver novelty item, but it does serve a useful purpose. My guess is that it's about 2 inches (5.08cm) long and 1.5 inches (3.81cm) wide. Probably made in the 20th century. What is it called?
A turtle was actually fairly common, as was a mouse. Some of the rarer ones I have seen were a bat, a spider, and, rather bizarrely, a human finger (you pulled on the nail). .