The Mystery of the Monster Larva Solved

Photo: Darryl L. Felder

For two hundred years, scientists have wondered what the monster larva Cerataspis montrosa (above) pulled from the guts of fish would look like when it's all grown up. Well, mystery solved:

"It's very exciting to have solved a nearly 200-year-old conundrum," Keith Crandall, a biology professor at George Washington University, said in a statement.
Drawing from genetic evidence, Crandall reported in the journal Ecology and Evolution this month that the larva, Cerataspis monstrosa, is actually a baby version of the deep-water aristeid shrimp known as Plesiopenaeus armatus.
Making this match-up between the baby and adult forms was not as easy as finding a larger version of the larva. In fact, the two couldn't look more different, the researchers said. C. monstrosa has a thick body covered in armor with "exceptional horn ornamentation," the researchers write. Yellowfin and blackfin tuna and dolphins prefer this "monstrous and misshapen animal," as the larva was called, for prey — and it was in these predators' gut contents that scientists had encountered the monster larvae.

LiveScience has the story: here.