In the 1800s, scientists found a 400-million-year-old fossil fish they thought could be the missing link between aquatic and land-dwelling creatures. They would have loved to study it, but it had gone extinct with the dinosaurs.

Or so they thought. Until 1938, when a museum curator saw a fisherman haul one out of his net in South Africa. She wrote a hasty telegram to her museum. They wrote back: “Get that fish!”

She had found the coelacanth, not extinct after all, but hiding for millions of years in the Indian Ocean.

True to the fossil, it had small pectoral fins, on arm-like stalks, connected to joints like shoulders, and a wide fleshy tail.

According to local reports, it was so oily and foul tasting that anyone who tried to eat it would become sick. Which probably helped this slow growing living fossil keep on living.

And researchers soon found it’s very slow indeed. Coelacanths can grow to 200 pounds and live to 100 years but don’t reach sexual maturity until they hit 50.

Females incubate eggs within their abdomen, which take 5 years to hatch, then emerge as live young—the longest gestation of any animal.

It turns out, however, the coelacanth wasn’t the missing link that scientists hoped for. That honor belongs to its relative, the lungfish, which crawls out of the water to make short journeys on land.