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Taxonomy C

Class

/ /klɑːs/ /
Etymology: From Latin classis — "division, fleet"
Quick Definition

A major taxonomic rank above order; fish belong primarily to Actinopterygii (ray-finned fishes) or Chondrichthyes (cartilaginous fishes).

📖 Full Definition

Class is the taxonomic rank between order and phylum. The major fish classes are: Actinopterygii (ray-finned bony fishes — 99% of all fish species), Sarcopterygii (lobe-finned bony fishes — coelacanths, lungfishes), Chondrichthyes (cartilaginous fishes — sharks, rays, chimaeras), Actinistia (coelacanths, sometimes included in Sarcopterygii), Myxini (hagfishes), and Petromyzontida (lampreys). Together these groups make fish the most diverse vertebrate class.

💡 Examples & Context

Atlantic salmon (Salmo salar) belongs to Class Actinopterygii (ray-finned fishes).