Cnidaria · cnidarians

Elkhorn coral

Acropora palmata

Acroporidae · staghorn & table coralsIUCN: Critically Endangered
Elkhorn coral
Photo: Author not stated on Commons · Public domain · Wikimedia Commons · resized

A Caribbean coral with flattened, antler-like branches that builds shallow reef crests.

Fun factIts reef crests break waves and help protect coastlines from storm surge.

Waters
Tropical Atlantic & Caribbean
Depth zone
Coral reefs
Diet
Plankton & symbiotic algae
Size
Colonies up to 4 m across

Classification

Cnidaria › Anthozoa › Scleractinia › Acroporidae

  1. Kingdom Animalia animals
    • Many-celled organisms that eat other living things for energy (heterotrophs)
    • Cells have no cell walls
    • Most can move at some stage of life
  2. Phylum Cnidaria cnidarians
    • Radially symmetric bodies with one opening that is both mouth and anus
    • Stinging cells (cnidocytes) fire tiny harpoons (nematocysts)
    • Two body forms: an attached polyp and a swimming bell (medusa)
  3. Class Anthozoa corals & anemones
    • Live only as polyps; there is no swimming jellyfish stage
    • Gut is divided by internal walls (mesenteries)
    • Includes corals and sea anemones
  4. Subclass Hexacorallia stony corals & anemones
    • Tentacles and internal walls come in multiples of six
    • Includes stony corals and sea anemones
  5. Order Scleractinia stony corals
    • Polyps build a hard limestone skeleton (calcium carbonate)
    • Many reef species host algae (zooxanthellae) that feed them through photosynthesis
    • Main builders of coral reefs
  6. Family Acroporidae staghorn & table corals
    • Fast-growing branching, table, or plate-shaped corals
    • Small polyps, with one larger polyp at each branch tip (axial corallite)
  7. Genus Acropora
    • Species in the same genus are very close relatives and often look alike.
  8. Species Acropora palmata Elkhorn coral

Closest relatives in the guide