Largest family of marine fish

The largest zoological family of marine fishes is Gobiidae, the goby family, which contains over 1,400 species, housed in more than 160 genera as of October 2023. Many are extremely small (some are less than 1 cm long when fully grown), even the largest rarely exceed 30 cm long, and they are generally characterized by the presence of a disc-shaped sucker derived from their fused pelvic fins. This means that gobies represent about 4% of all living fish species (c. 34,000).

Despite being marine fish, a number of goby species have evolved to survive in brackish water and some even in freshwater habitats.

The largest family of fish overall is Cyprinidae, the carp family, with approximately 1,790 species housed in 160 genera. All freshwater dwellers, among its most familiar members are the carps (including goldfishes), barbs, minnows and barbels.