Charlotte, a stingray with no male companion, is pregnant in her mountain aquarium

Charlotte, a rust-colored stingray the size of a serving platter, has spent much of her life gliding around the confines of a storefront aquarium in North Carolina’s Appalachian Mountains.

She’s 2,300 miles (3,700 kilometers) from her natural habitat under the waves off southern California. And she hasn’t shared a tank of water with a male of her species in at least eight years.

And yet nature has found a way, the aquarium’s owner said: The stingray is pregnant with as many as four pups and could give birth in the next two weeks.

“Here’s our girl saying, ’Hey, Happy Valentine’s Day! Let’s have some pups!” said Brenda Ramer, executive director of the Aquarium and Shark Lab on Main Street in downtown Hendersonville.

An expert on the stingrays said it would have been impossible for Charlotte to have mated with one of the five small sharks that share her tank, despite news reports suggesting that was the case after Ramer joked about a possible interspecies hookup.

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

Its biggest lesson now is on the process of parthenogenesis: a type of asexual reproduction in which offspring develop from unfertilized eggs, meaning there is no genetic contribution by a male.

The mostly rare phenomenon can occur in some insects, fish, amphibians, birds and reptiles, but not mammals. Documented examples have included California condors, Komodo dragons and yellow-bellied water snakes.

Kady Lyons, a research scientist at the Georgia Aquarium in Atlanta who is not involved with the North Carolina aquarium, said Charlotte’s pregnancy is the only documented example she’s aware of for this species, round stingrays.

But Lyons isn’t at all shocked. Other kinds of sharks, skates and rays — a trio of animals often grouped together — have had these kinds of pregnancies in human care.

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

To be clear, Lyons said, these animals are not cloning themselves. Instead, a female’s egg fuses with another cell, triggers cell division and leads to the creation of an embryo.