An ostracod encased in amber preserves what may be the oldest known fossilized sperm
Ostracods look like nothing more than seeds with legs. But some species of these tiny crustaceans have an outsize claim to fame: giant sperm. In the most extreme case, it can stretch 1.18 centimeters, over three times the length of an adult.A single piece of amber from Myanmar held 39 ostracods, including many from a newly discovered species, Myanmarcypris hui. Using micro-CT scans, Dave Horne, a micropaleontologist at Queen Mary University of London, and colleagues peered inside a few of the tiny shelled animals.
“We knew from looking at the piece of amber with an ordinary light microscope that there were antennae and legs sticking out of the shell, so we were hopeful of finding internal organs,” Horne says. If delicate parts like legs and antennae are preserved, it’s likely that other soft parts are too, he says. “But what we saw … exceeded expectations.”
