Fossils suggested these ancient marine predators grew to about 2 feet (0.6 meters) long. Prior studies also suggested they died out at the end of the Cambrian.
Now, extraordinarily well-preserved fossils unearthed in the rocky desert in southeastern Morocco by local collector Mohammed Ben Moula reveal giant anomalocaridids that measured more than 3 feet (1 m) in length.
“The Moroccan specimens are the largest anomalocaridids known to date — they are about double the size of their Cambrian counterparts,” Van Roy told LiveScience. “There have been suggestions of Cambrian anomalocaridids of over 6 feet (2 meters) in length, but these estimates are extrapolations from very fragmentary material, and hence not too reliable.”
Story: Charles Q. Choi | Photo: Esben Horn