FaunaHub

Coelacanth (genus Latimeria)

Marine fishLobe-finnedLiving fossil

Preserved coelacanth (Latimeria chalumnae) specimen on display at a natural history museum.

Coelacanth (Latimeria chalumnae) — museum specimen.

Image: Jakub Hałun, CC BY-SA 4.0, via Wikimedia Commons.

Overview

The coelacanth (genus Latimeria) is one of the most famous fish in the world — a large, deep-water, lobe-finned fish long known only from fossils and assumed to have died out tens of millions of years ago, until a living one was caught off South Africa in 1938. Its rediscovery was one of the great zoological surprises of the twentieth century.

Two living species are recognised: the West Indian Ocean coelacanth (Latimeria chalumnae) and the Indonesian coelacanth (Latimeria menadoensis). Coelacanths belong to the lobe-finned fishes, the group more closely related to four-limbed land vertebrates than to typical ray-finned fish.

Conservation note: coelacanths are of serious conservation concern — the West Indian Ocean species in particular is considered critically endangered — and they are protected. Verify each species' current status at iucnredlist.org.

Habitat & Range

Coelacanths live in deep, cool waters along steep ocean slopes, sheltering by day in underwater caves and ledges at depth and moving to feed at night. Populations are known from parts of the western Indian Ocean (including around the Comoros) and from Indonesian waters.

Diet

Coelacanths are carnivores that feed on fish and cephalopods such as squid. They are slow, drifting hunters that are thought to use a passive “drift-feeding” approach, conserving energy in their deep, cold habitat rather than chasing prey actively.

Behavior

Coelacanths move with a distinctive style, paddling with their fleshy, limb-like lobed fins in a coordinated pattern. They shelter communally in caves during the day. They are slow-growing and long-lived, give birth to live young after a very long gestation, and have changed relatively little in overall body plan over a vast span of geological time — which is why they are described as “living fossils.”

Human Interaction & Conservation

Coelacanths are of immense scientific interest for what they reveal about the evolution of lobe-finned fishes and the origins of land vertebrates. They are rare, slow to reproduce, and vulnerable to accidental capture in deep-set fishing gear, which makes their small populations fragile. Conservation and legal protection are in place; for current, species-specific status, consult the IUCN Red List.

More photos of the coelacanth

Coelacanth holotype specimen showing the lobed fins.

Coelacanth (Latimeria chalumnae), showing the lobed fins.

Image: Bernard DUPONT, CC BY-SA 2.0, via Wikimedia Commons.

Frequently Asked Questions — Coelacanth

Why is the coelacanth called a living fossil?
Coelacanths were known only from fossils and were thought to have gone extinct tens of millions of years ago — until a living one was discovered in 1938. Because the modern fish retains a body plan broadly similar to ancient relatives, it is popularly called a "living fossil," though it is a fully modern, evolving animal.
How many kinds of coelacanth are there?
Two living species are recognised: the West Indian Ocean coelacanth (Latimeria chalumnae) and the Indonesian coelacanth (Latimeria menadoensis). Both are deep-water fish, found in different parts of the world.
Is the coelacanth related to land animals?
Yes, in a broad evolutionary sense. Coelacanths are lobe-finned fishes, a group more closely related to the ancestors of four-limbed land vertebrates (tetrapods) than to the familiar ray-finned fishes. This is part of why they are so scientifically important.
Are coelacanths endangered?
Yes. Coelacanths are of serious conservation concern — the West Indian Ocean species is considered critically endangered — owing to their rarity, slow reproduction, and vulnerability to accidental capture. Status should be checked per species against current IUCN Red List data.

Sources and further reading

Authoritative wildlife references used for general educational context. Conservation status should always be verified against current IUCN Red List data. External links open in a new tab.