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| synonyms = (Defunct species:)〔 }} ''Anomalocaris'' ("abnormal shrimp") is an extinct genus of anomalocaridid, a family of animals thought to be closely related to ancestral arthropods. The first fossils of ''Anomalocaris'' were discovered in the ''Ogygopsis'' Shale by Joseph Frederick Whiteaves, with more examples found by Charles Doolittle Walcott in the famed Burgess Shale. Originally several fossilized parts discovered separately (the mouth, feeding appendages and tail) were thought to be three separate creatures, a misapprehension corrected by Harry B. Whittington and Derek Briggs in a 1985 journal article.〔 ==Anatomy== ''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", maximizing the swimming efficiency. The construction of a remote-controlled model showed this mode of swimming to be intrinsically stable, implying that ''Anomalocaris'' would not have needed a complex brain to manage balance while swimming. The body was widest between the third and fifth lobe and narrowed towards the tail; it had at least 11 lobes in total.〔 It is difficult to distinguish lobes near the tail, making an accurate count difficult.〔 ''Anomalocaris'' had a large head, a single pair of large, compound eyes on stalks comprising approximately 16,000 lenses, 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 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 through 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 gigantic, up to two meters long.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「anomalocaris」の詳細全文を読む スポンサード リンク
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