First completely original Anomalocaris - Fund, from the Royal Ontario Museum

  • North America (Canada ( Burgess Shale ), USA, Greenland)
  • Asia (China)
  • Australia
  • Anomalocaris saron
  • Anomalocaris canadensis
  • Anomalocaris kunmingensis

Anomalocaris ( " abnormal shrimp " ) is a genus of Anomalocarida, a group of extinct, marine, invertebrates without fixed systematic classification, the arthropods ( Arthropoda ) may be closely related. Anomalocaris was in the time of the early and middle Cambrian before 530-501 million years ago, with a length between 60 and 120 centimeters, the largest animal known from that time.

Body characteristics

Anomalocaris was swimming in the water and used movable flap-like appendages on the body to get around. His head had a pair of up to 3 cm in size, perhaps interconnected, long stalked eyes. These were of several hundred or even several thousand lenses are made and had in its structure similar to the compound eyes of today's insects and crustaceans. Thus, they were among the largest and sharpest ever existing visual organs.

With two exceptionally movable grippers on the disc-shaped mouth opening Anomalocaris was probably to grab prey and able to convey to his mouth. However, recent research suggests that the mouth of Anomalocaris was not suitable for eating hard food because it had no teeth, but only soft horn plates. In addition, the mouth did not close, suggesting that Anomalocaris has only sucked his food under certain circumstances.

Reconstruction and related genera

Anomalocaris was often misclassified. Thus isolated fossil finds of the circular mouth were kept for a jellyfish and called Peytoia. The body is believed to be a sponge and gave him the name Laggania. Likewise, the grippers have been described as a Arthropodengattung. Ultimately, however, the animal Anomalocaris could be reconstructed. After further fossils in the Burgess Shale, the image of the beast clearer, later it was discovered with Anomalocaris saron in China another kind, next to the American Anomalocaris was canadiensis. Likewise, other related genera have been described, including for example Amplectobelua, also a Chinese Anomalocaride. Another representative of the Anomalocariden Reference is made to Schinderhannes bartelsi - especially because this about 100 million years later lived in the lower Devonian and thus greatly expands the geological lifetime of this group.


Due to many unique characteristics is still not fixed, where the Anomalocariden, which now form their own family, are to be classified in the classification of invertebrates. It was created, in which one attempts to accommodate the Anomalocariden and their relatives, such as Opabinia an order that Radiodonta; into a strain or even a class they are concrete but not yet classified. One proposed solution for this was the creation of the class Dinocaridita, which is the parent of the Radiodonta, and the classification of these. Lobopoden in the trunk of the However, this is usually regarded as a not yet existing approach. They may form a side branch of the arthropods, the already split off at the start of the early Cambrian and specialized.