How to Identify Invertebrates on Live Rock
- 1). Identify anemones. The base of an anemone will be attached to the rock, while the body of the creature resembles a flower made of a jelly-like substance. Anemones have many petals, or tentacles, that surround an open center mouth. These tentacles are controlled by the animal, and will open and close at will. Anemones live in most marine environments and are partial to crevices in rocks. Look for anemones in spots that are deep enough that they are never exposed to air.
- 2). Identify sea urchins. Sea urchins attach to rocks like anemones, but are balls of brittle, sharp needles. Urchins are capable of movement, but are not flexible like anemones. Urchins also favor crevices in the rock, for safety and protection, and live in areas that are consistently under water.
- 3). Identify starfish. Starfish are star-shaped creatures with hardened exoskeletons that come in numerous colors. Look for starfish in cracks and on the bottoms of pools. Starfish are quite flexible, and will have rows of suction cups on the undersides of their arms for moving along the rock. Because starfish are mobile creatures, they can be found in various depths of water. These creatures can live out of water for a short period of time, so won't necessarily be buried deep at the bottom of pools.
- 4). Identify barnacles. Barnacles are hard, cup-shaped creatures that attach their open ends to rock in most marine environments. Look carefully--they will grow in groups of many barnacles, and appear to be extensions of the live rock due to their lack of movement and color. Barnacles can survive for long periods of time outside of the water, and can usually be found in very shallow areas.
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