Coelacanths and Lungfishes: Sarcopterygii

Physical characteristics: Coelacanths have fleshy fins. Instead ofbeing made up of individual bones, or vertebrae (ver-teh-BREE), the backbone is a stiff tube. Coelacanths are bluish gray with white mark-ings. They weigh 110–198 pounds (50–90 kilograms). Female coela-canths can be as long as 6 feet (1.9 meters) and males as long as 5 feet (1.50 meters).

Geographic range: Coelacanths live on both sides of the Indian Ocean.

Coelacanths eat whatever they find as they drift in the current. (©Peter Scoones/Photo Researchers, Inc. Reproduced by permission.)

Habitat: Coelacanths live in caves in tropical oceans below 328 feet (100 meters), in steep, sloping areas. At night they move up the slope to feed.

Diet: Coelacanths eat whatever they find as they drift in the current. Because they can lift the upper jaw as well as move the lower jaw, coelacanths can open their mouths quite far to suck prey from crevices.

Behavior and reproduction: While swimming, coelacanths move their pectoral (PECK-ter-uhl) and pelvic fins the way most four-footed animals move their legs. The pectoral fins are the front pair, and the pelvic fins are the rear pair. Coelacanths give birth to live young, but scientists do not know how they what sort of mating takes place. The gestation (je-STAY-shun) period, or time the young develops inside the female, is about thirteen months. Scientists believe females become mature for the first time when they are more than twenty years old.

Coelacanths and people: Coelacanths are valued for the information they can provide about evolution.

Conservation status: The World Conservation Union (IUCN) lists one species of coelacanth as Critically Endangered, meaning that it faces an extremely high risk of extinction in the wild in the near future. ∎