Coelom metamerism in Echinodermata

Авторы: Ezhova O.V., Malakhov V.V.
Журнал: Paleontological Journal
Том: 55
Номер: 10
Год издания: 2021
Издательство: Pleiades Publishing, Inc.
Местоположение издательства: New York, USA
DOI: 10.1134/S0031030121100038
Аннотация: Within all major taxa of Bilateria, there are forms with coelomic metamerism. This suggests thatcoelomic metamerism was characteristic of the common ancestor of Bilateria. Among deuterostomes, metamerism is clearly expressed in chordates, and elements of metamerism are present in hemichordates. Do echinoderms have remnants of coelomic metamerism that was inherited from the common ancestor of Bilateria? The coelomic system of echinoderms includes several metameric coelomic rings located along the oral-aboral axis, namely: the axocoelomic ring, the hydrocoelomic ring, 2 to 6 coelomic rings originating from the left somatocoel, and one epigastric ring originating from the right somatocoel. Thus, in echinoderms, there is adissymmetrical metamerism, derived from the original metamerism of the common ancestors of Deuterostomia and, possibly, the common ancestors of Bilateria. The problem of dexiothetism as the cause for the formation of coelomic dissymmetry in echinoderms is discussed.
Добавил в систему: Ежова Ольга Владимировна

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