According to Business Insider article a report published today in the Journal of Fish Biology documents the first known discovery of a two-headed bull shark fetus (Carcharhinus leucas). The two-headed fetus was discovered in the Gulf of Mexico in 2011, off the Florida coast. The shark fetus, along with multiple other live fetuses, was removed live from its mother by a fisherman. However, it died soon after being removed. According to the report, the fetus was a single shark with two-heads as opposed to being “conjoined twins.” It is the first known recorded case of a bull shark with two heads.
For more information, including photos of the shark fetus, check out the story at Business Insider.
You can also view the abstract at the Journal of Fish Biology.