marine iguana

lizard

Also known as: Amblyrhynchus cristatus

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Last updated

July 23, 2026

Quick Summary

The marine iguana (Amblyrhynchus cristatus) is a unique lizard species found exclusively on the Galapagos Islands. These iguanas are distinguished by their ability to forage for food in the sea, primarily feeding on underwater algae. They possess flattened tails that aid in swimming and diving, and their scales are typically black to ashen-gray. While most iguanas are herbivores that inhabit tropical forests and grasslands, the marine iguana's adaptation to a marine environment makes it a remarkable exception within the lizard family.123

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lizard
General features
One living lizard, the marine iguana (Amblyrhynchus cristatus) of the Galapagos Islands, feeds on algae in the sea. However, it spends much of its time basking on lava rocks on the islands. No other extant lizard species is marine, but several are partially aquatic and feed on freshwater organisms.
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One living lizard, the marine iguana (Amblyrhynchus cristatus) of the Galapagos Islands, feeds on algae in the sea. However, it spends much of its time basking on lava rocks on the islands. No other extant lizard species is marine, but several are partially aquatic and feed on freshwater organisms.
Read More