A pair of stripy “alien” sharks have been caught mating in unusual footage captured during Discovery’s Shark Week. The footage features two Pyjama sharks ( Poroderma africanum) when they wrap around each other and fall onto the ocean floor before dispersing. It’s probably the first time that species has been captured mating.

“In “Alien Sharks: Strange New Worlds,” biologist and adventurer Forrest Galante explores a few of South Africa’s lesser-known species of sharks. Many of them haven’t changed in the open for millions of years.

The film follows Galante going into the kelp woods, where pajama sharks live, as he catches an endangered wedgefish with a white-spotted pattern ( Rhynchobatus australiae) to protect it and resolves the puzzle of where the region’s ancient, broadnose sevengill sharks ( Notorynchus cepedianus) are, being virtually extinct from the area.

In among the most fascinating moments of the show, Galante and his crew observe sharks mating. The footage of sharks having a mating session in nature has been recorded a few times. In courtship, a male will attack the female’s fins and back to secure her. Then, he uses his claspers, calcified appendages protruding through the pelvic floor, to transfer sperm into the female. Eggs fertilize inside the female’s body before becoming laid or developing in the womb.

“I think we’re the first ones to ever record [pyjama sharks mating],” Galante said to Live Science. “Honestly, just seeing it… I’m getting goosebumps thinking about it because it was such an amazing experience to see this first hand.”

He claimed that one camera operator had seen the two sharks and assumed they might be fighting. “I saw the male grasped onto the female and I could see him starting to wind his body. So I knew immediately what they’re doing,” Galante stated. The group sat briefly before the couple fell to the floor and completed the copulation. “Then just as quickly as it started, you just see him let go and boom, they’re both gone. And that was it, it was all over.”

The footage was shot in the oceans of the Great African Seaforest — the only bamboo and kelp ( Ecklonia maxima) forest on Earth that extends several hundred miles across the southern tip of South Africa to Namibia. It is a significant ecosystem, sustaining a vast variety of species. Climate changes threaten kelp forests in other regions, but South Africa’s seems to be flourishing.

In the film, pajama sharks mating within the same habitat, Galante said, indicate that the ecosystem is flourishing. “These sharks are not only surviving, but they’re reproducing, which is a fantastic sign,” Galante declared in the show.