Cleaner shrimp (Silke Baron / CC BY)
Shrimps (or prawns) are slender crustaceans that are well adapted for swimming. The ventral part of their long muscular abdomen supports pleopods (swimming legs). With their robust legs, lobsters and spiny lobsters are well adapted for walking on the ocean floor. In contrast to crabs, they do not walk sideways. Spiny lobsters lack the large claws. In general, lobsters are 25–50 centimeters (10–20 inches) long.