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Anatomy A ~34,000 species

Actinopterygian

/ /ˌæktɪnɒpˈtɛrɪdʒɪən/ /
Etymology: From Greek aktis (ray) + pteryx (fin/wing)
Quick Definition

A ray-finned fish; member of Actinopterygii, the class containing 99% of living fish species.

📖 Full Definition

Actinopterygii (ray-finned fishes) is the largest class of vertebrates, containing over 34,000 species. Unlike lobe-finned fishes (Sarcopterygii), their fins are supported by bony spines (rays) rather than fleshy, limb-like lobes. The class is subdivided into basal groups (polypteriforms, sturgeons, gars, bowfin) and the highly derived Teleostei. Ray-finned fishes dominate virtually every aquatic environment on Earth and represent the vast majority of commercially exploited fish species.