Chordata · chordates

Marine iguana

Amblyrhynchus cristatus

Iguanidae · iguanasIUCN: Vulnerable
Marine iguana
Photo: RAF-YYC from Calgary, Canada · CC BY-SA 2.0 · Wikimedia Commons · resized

The only lizard that forages in the sea, found only in the Galápagos.

Fun factIt sneezes out excess salt through nasal glands.

Waters
Eastern Pacific
Depth zone
Intertidal shore, Coastal shallows & estuaries
Diet
Marine algae
Size
Up to 1.3 m

Classification

Chordata › Reptilia › Squamata › Iguanidae

  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. Clade Bilateria bilateral animals
    • Body has a left and right side that mirror each other (bilateral symmetry)
    • Head end with concentrated nerves; three tissue layers
    • Includes about 99% of all living animal species
  3. Clade Deuterostomia deuterostomes
    • In the embryo, the first opening becomes the anus and the mouth forms second
    • Includes echinoderms and chordates
  4. Phylum Chordata chordates
    • At some stage of life: a stiffening rod along the back (notochord)
    • A hollow nerve cord along the back (dorsal)
    • Slits in the throat (pharyngeal slits) and a tail past the anus
  5. Subphylum Vertebrata vertebrates
    • A skull (cranium) protecting a brain
    • Backbone or similar support around the nerve cord
    • Includes fishes, amphibians, reptiles, birds, and mammals
  6. Infraphylum Gnathostomata jawed vertebrates
    • Jawed vertebrates: jaws formed from gill arches
    • Paired fins or limbs
    • Includes all fishes except hagfish and lampreys, plus all tetrapods
  7. Superclass Osteichthyes bony vertebrates
    • Bony vertebrates: skeleton made largely of bone
    • Most have a lung or swim bladder
    • Includes ray-finned and lobe-finned fishes and all tetrapods
  8. Clade Sarcopterygii lobe-finned vertebrates
    • Lobe-finned: fleshy fins with bones like those of limbs
    • Includes coelacanths, lungfishes, and all tetrapods
  9. Clade Tetrapoda four-limbed vertebrates
    • Four limbs with fingers and toes (or descended from animals that had them)
    • Breathe air with lungs
  10. Class Reptilia reptiles (birds included)
    • Scaly skin made of keratin
    • Lay shelled eggs on land or carry eggs inside the body (amniotic egg)
    • In modern classification this group includes birds
  11. Order Squamata lizards & snakes
    • Lizards and snakes: skin shed in pieces or whole
    • Flexible skull with a hinged jaw
    • Males have paired reproductive organs (hemipenes)
  12. Family Iguanidae iguanas
    • Iguanas: stout lizards with crests of spines along the back
  13. Genus Amblyrhynchus
    • Species in the same genus are very close relatives and often look alike.
  14. Species Amblyrhynchus cristatus Marine iguana

Closest relatives in the guide