Coelacanth

• It was believed to have died out 65 million years ago until it was rediscovered alive in 1938.
• A 2021 study found its lifespan had been underestimated fivefold, reaching around 100 years.
• It has the longest gestation known in any vertebrate, of roughly five years.
• historia naturalIt was believed to have died out some 66 million years ago until a live specimen was caught in 1938 off the coast of South Africa.

Skeleton type

Vertebrate - partly cartilaginous internal skeleton with primitive bony elements (lobe-finned fish)

Habitat & environment

Deep submarine caves (100-700 m) in the warm waters of the western Indian Ocean, mainly around the Comoros

Birth weight

31-38 cm long at birth (the young already well developed)

Size at birth

31 - 38 cm long at birth

Sexual maturity

Reassessed in 2021 at between 40 and 69 years (an earlier study suggested 20-plus; it is now known to be far later)

Gestation / incubation

Roughly 5 years, the longest gestation known in any vertebrate

Litter / clutch size

5 to 29 live young per litter (an ovoviviparous species)

Sources consulted: Sci-News.com (Current Biology study); NOAA Fisheries; Animal Diversity Web; FishBase; ResearchGate (growth study); EarthDate; ScienceDirect

Best time: All year round in the volcanic caves of the Comoros and South Africa, between 150 and 250 m deep, at night; it can only be seen from submersibles.