"Really! I was born that way! I swear!" A new species of shark was discovered in California recently, called the Eastern Pacific black ghostshark. It's part of a group known as big black chimeras, and members of the species have actually been laying around pickled in museums since the 1960s—but only recently have scientists realized that the black ghostsharks were in fact a separate species. One possibility is that past scientists were too distracted by the sharks', er, highly unusual feature that they lumped them in with the other chimeras. Douglass Long, author of the study (PDF) detailing the new species, described the shark to National Geographic News:
Male chimeras...have retractable sexual appendages sprouting from their foreheads. These organs, which resemble a spiked club at the end of a stalk, may be used to stimulate a female or to pull her closer—though these are still assumptions, Long said.
So basically these guys have a mace swinging from their forehead that they use to club female sharks. Talk about a remarkable trick of animal mating. Related Content: Discoblog: In Competitive Sex, Male Butterflies Employ “Dipstick Method” Discoblog: Everything You Ever Wanted to Know About Squid Sex Discoblog: Internet Dating a New Option for Zoo Animals