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beryciformes
An order of somewhat intermediate position among actinopterygian fishes. It shares with the perciforms fin spines and ctenoid scales, an upper jaw bordered by the premaxillae, a ductless swim bladder, and absence of a mesocoracoid. An orbitosphenoid bone is present, as is typical of many lower teleosts. The pelvic fins are thoracic or subabdominal in position, and each has a spine and 3 to 13 (usually more than 5) soft rays; the pelvic girdle is most often attached to the cleithra; and there are 18 or 19 principal caudal rays.
- 词性: noun
- 行业/领域: 科学
- 类别 普通科学
- Company: McGraw-Hill
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- Francisb
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