Ostracod fossil

The ostracod Luprisca incuba was discovered in 450-million-year-old rocks in New York State. (University of Leicester)

Scientists have uncovered a new fossil species preserved in a way that reveals how parents took care of their young 450 million years ago.

A team comprised of scientists from the U.S., U.K. and Japan discovered a new species of a fossil ostracod — a group related to crabs, shrimps and lobsters — in mudstone rocks from New York State.

Ostracods are tiny crustaceans that live in lakes, ponds, rivers and oceans.

Scientists used X-ray techniques to examine the fossils, which are preserved in pyrite.

What they discovered, the scientists said in the study published in the journal Current Biology, was a “nursery in the sea" in which the species were preserved incubating their eggs together with some eggs already hatched.

"This a very rare and exciting find from the fossil record,” said David Siveter, a professor of paleontology at the University of Leicester in Britain.

“Only a handful of examples are known where eggs are fossilized and associated with the parent. This discovery tells us that these ancient tiny marine crustaceans took particular care of their brood in exactly the same way as their living relatives."

Researchers say their find marks what they say is the oldest evidence of a reproductive and child-care strategy of any species.

The newly unearthed fossils are only two to three millimetres long and are said to be “exceptionally well-preserved,” complete with the shell and also the soft parts of the animal within the shell.

The scientific team — which included researchers from the universities of Yale and Kansas, Oxford and the Japan Agency of Marine Science and Technology — named the new species Luprisca incuba after Lucina, the goddess of childbirth, and incuba, indicating the mother was sitting, incubating, her eggs.