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fishes image

fishes
Cold-blooded aquatic vertebrates (about 30,000 species) having motor fins and bodies that are usually covered in scales.


cartilaginous fish image

cartilaginous fish
Fish whose skeleton is made of cartilage rather than bone; its skin is covered in hard scales called denticles. There are currently 700 species.


bony fish image

bony fish
Fish with a rigid skeleton and smooth flat scales; the 20,000 present-day species make up the largest group of fish.