Anomalocaris

Anomalocaris ("abnormal shrimp") is an extinct genus of anomalocaridid, which are, in turn, thought to be closely related to the arthropods along with Opabinia and Marrella (Unknown if it's phylum was Arthropod). Other Lobopods includes Hallucigenia, Opabinia and Aysheaia. Other Carnivores of the Burgess Shale include Priapulids (Stem-Group), Hurdia, Peytoia and Opabinia. Anomalocaris lived with Hallucigenia and Wiwaxia and they both first lived in Chengjiang.

Description
Anomalocaris is thought to have been a predator. It propelled itself through the water by undulating the flexible lobes on the sides of its body. Each lobe sloped below the one more posterior to it,and this overlapping allowed the lobes on each side of the body to act as a single "fin", maximising the swimming efficiency.The construction of a remote-controlled model showed this mode of swimming to be intrinsically stable,meaning that Anomalocaris need not have had a complex brain to cope with balancing while swimming. The lateral lobes overlapped. The widest part of the body was on the third to fifth lobe; it narrowed towards its tail, and had at least 11 lobes in total.The more posterior lobes are difficult to discriminate, making an accurate count difficult.Anomalocaris had a large head, a single pair of large, possibly compound eyes, and an unusual, disk-like mouth. The mouth was composed of 32 overlapping plates, four large and 28 small, resembling a pineapple ring with the center replaced by a series of serrated prongs.The mouth could constrict to crush prey, but never completely close, and the tooth-like prongs continued down the walls of the gullet.Two large 'arms' (up to seven inches in length when extended) with barb-like spikes were positioned in front of the mouth.The tail was large and fan-shaped, and along with undulations of the lobes, was probably used to propel the creature thro ROM-BurgessShale- CompleteAnomalocarisFossil.png ugh Cambrian waters.Stacked lamella of what were probably gills attached to the top of each lobe.

For the time in which it lived Anomalocaris was a truly gigantic creature, reaching lengths of up to one meter.

Anomalocaris had a cosmopolitan distribution in Cambrian seas, and has been found from early to mid Cambrian deposits from Canada, China, Utah and Australia, to name but a few. Peytoia and Hurdia are other anomalocarids.

A long-standing view holds that Anomalocaris fed on hard-bodied animals, including trilobites. While its mid-gut glands strongly suggest a predatory lifestyle, its ability to penetrate mineralised shells has come under fire in recent years.Some Cambrian trilobites have been found with round or W-shaped "bite" marks, which were identified in shape with the mouthparts of Anomalocaris. Opabinia could also fed on other creatures like Aysheaia and Hallucigenia but not Anomalocaris or a another giant predator like Hurdia with it's long gut. They are the biggest animals of the Burgess Shale and bigger than other Early and Middle Cambrian animals.

In the Media
Anomalocaris was in the documentary Walking with Monsters, which is made from the same creators of Walking with Dinosaurs. In this documentary, it takes us back in time to the Cambrian when this fearsome predator ruled, and it shows us how it hunted an lived.