Miracle conception: Charlotte the single stingray is pregnant

The rust-coloured ray is pregnant with as many as four pups. Credit: AP

Charlotte the stingray has caused shock in her aquarium after she became pregnant despite not having met a male of her species for at least eight years.

The rust-coloured ray is pregnant with as many as four pups, the aquarium's owners have said, and she could give birth in the next two weeks.

Charlotte spends her days floating around a storefront aquarium in North Carolina's Appalachian Mountains with five small sharks, but experts have suggested an interspecies romance is unlikely to have occurred.

The most probable explanation for Charlotte's condition is parthenogenesis, which is a type of asexual reproduction by which offspring develop from unfertilised eggs.

Kinsley Boyette, assistant director of the Aquarium and Shark Lab by Team ECCO, poses next to Charlotte. Credit: AP

The form of reproduction, which doesn't require any contribution from a male, can be experienced by some insects, fish, amphibians birds and reptiles.

Charlotte's case is the only documented example of the phenomenon occurring in a stingray, Kady Lyons, a research scientist at the Georgia Aquarium in Atlanta, said.

“We don’t know why it happens,” Lyons said. “Just that it’s kind of this really neat phenomenon that they seem to be able to do."

“I’m not surprised, because nature finds a way of having this happen,” she added.

The pregnancy came as a total shock to Brenda Ramer, executive director of the Aquarium and Shark Lab on Main Street in downtown Hendersonville.

“We were all like, ’Shut the back door. There’s no way,” Ms Ramer said. ”We thought we were overfeeding her. But we were overfeeding her because she has more mouths to feed.”

Charlotte's natural habitat would be a home under the waves of southern California, around 2,300 miles away from her artificial abode at the aquarium.

“Here’s our girl saying, ’Hey, Happy Valentine’s Day! Let’s have some pups!” Ms Ramer said.

The small aquarium is run by Ms Ramer's educational nonprofit, Team ECCO, which encourages local schoolchildren and others to take an interest in science.

They now plan to double the size of Charlotte's tank, which is currently around 2,200 gallons, to make room for the new arrivals.

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