Fish and crabs
| Body Structure | Streamlined, covered with scales |
| Size Range | Varies widely from a few centimeters to several meters |
| Coloration | Varies widely; can be brightly colored, patterned, or camouflaged |
| Locomotion | Fins for swimming |
| Respiratory System | Gills for extracting oxygen from water |
| Habitat | Freshwater, saltwater, and brackish environments |
| Diet | Carnivorous, herbivorous, or omnivorous; includes algae, plankton, smaller fish, and invertebrates |
| Reproductive System | Oviparous; lay eggs, which can be externally or internally fertilized |
| Sensory Organs | Well-developed eyes, lateral line system for detecting vibrations and pressure changes |
| Lifespan | Varies widely; can range from a few years to several decades depending on the species |
