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percopsiformes
An order of the Paracanthopterygii, a fish superorder of questionable monophyly. Percopsiforms are identifiable by the following combination of characters: nonprotractile premaxilla; tooth-bearing ectopterygoid and palatine bones; absence of a suborbital shelf, orbitosphenoid, and basisphenoid bones; weak spines usually present in the dorsal fin; and pelvic fins, if present, behind the pectoral fins. There are three families, seven genera, and nine species, all confined to freshwaters of North America.
- 词性: noun
- 行业/领域: 科学
- 类别 普通科学
- Company: McGraw-Hill
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创建者
- Francisb
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