An artists reconstruction of what Aegirocassis benmoulae would look like. The creature could exceed two meters in length, making it one of the largest arthropods known to science. (Image credit: Marianne Collins, ArtofFact)

An artists reconstruction of what Aegirocassis benmoulae would look like. The creature could exceed two meters in length, making it one of the largest arthropods known to science. (Image credit: Marianne Collins, ArtofFact)

New fossils from Morocco represent the earliest known giant filter-feeding sea creature, Aegirocassis benmoulae. These creatures could exceed two meters in length and fed on plankton much the same way modern whales do.

Scientists think the animals went extinct because there was not enough plankton at the time (around 450 million years ago) to allow such large creatures to survive.

The fossils also provide insights into crustaceans, insects and other modern arthropods’ evolution and history.They offer new insights in  the evolution of the animals’ trunk whose flaps bear a resemblance to both walking limbs found on insects and gill flaps of lobsters.

Original research paper published in Nature Paleontology on March 9, 2015.

Names and affiliations of selected authors

Peter Van Roy, Department of Geology and Geophysics, Yale University, New Haven, Connecticut, U.S.A.