These bedbugs belong to Walter Penny who uses them to train his dog Macaroni to find them. They are about the size of a capital "O" in this caption. Bedbugs are known for being small, elusive and nocturnal, making them difficult to detect. The name bedbug

These bedbugs belong to Walter Penny who uses them to train his dog Macaroni to find them. They are about the size of a capital "O" in this caption. Bedbugs are known for being small, elusive and nocturnal, making them difficult to detect. The name bedbug comes from their habit of living in mattresses and sofas. They feed on the blood of humans and other warm-blooded hosts. Karl Gehring/The Denver Post (Photo By Karl Gehring/The Denver Post via Getty Images)