Class Anthozoa - Sea Anemones and Corals

Life Cycle

No medusa stage; only polyp form

Septa

Internal partitions in the gastrovascular cavity that increase surface area

Siphonoglyph

Ciliated groove that moves water into the gastrovascular cavity

Pedal Laceration

Asexual reproduction - anemone leaves part of its pedal disc behind which grows a new individual

Acontia

Thread like structures armed with nematocysts; used in defense

Hermatypic Corals

Reef-building corals; secrete calcium carbonate skeletons (calcareous cup)

Zooxanthellae

Photosynthetic dinoflagellates living symbiotically in coral tissues; provide O2 and sugars; coral provides CO2 and H2O

Coral Bleaching

Loss of zooxanthellae due to stress (temp, pollution, disease) leading to coral death (5 mass events since 1998)