Meet the sturddlefish, an "impossible" hybrid

Scientists "accidentally created" a spiky-snouted hybrid of the Russian sturgeons and American paddlefish, which we are assured "shouldn't have been possible."

Hungarian scientists announced in May in the journal Genes that they had accidentally created a hybrid of the two endangered species, which they have dubbed the "sturddlefish." There are about 100 of the hybrids in captivity now, but scientists have no plans to create more.

"We never wanted to play around with hybridization. It was absolutely unintentional," Attila Mozsar, a senior research fellow at the Research Institute for Fisheries and Aquaculture in Hungary, told The New York Times.

From the paper's abstract:

The hybridization was repeated using eggs from three sturgeon and sperm from four paddlefish individuals. Survival in all hybrid family groups ranged from 62% to 74% 30 days after hatching. This was the first successful hybridization between these two species and between members of the family Acipenseridae and Polyodontidae. ... Although the growth performance showed high variance in hybrids (mean: 1.2 kg, SD: 0.55), many individuals reached a size of approximately 1 kg by the age of one year under intensive rearing conditions.