True gobies

Gobiinae
Didogobius schlieweni
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Perciformes
Family:	Gobiidae
Subfamily:	Gobiinae G. Cuvier, 1816

Gobiinae also known as the True gobies, are a subfamily of the goby family Gobiidae. They are found in all oceans and a few rivers and lakes, but most live in warm waters. Altogether, the Gobiinae unite about 1149 described species in 160 genera, and new ones are still being discovered in numbers.

They are usually mid-sized to small ray-finned fishes; some are very colorful, while others are cryptic. Most true gobies are less than 10 cm (4 in) long when fully grown. The largest species Glossogobius giuris can reach up to 50 cm (20 in); the smallest known species as of 2010, Trimmatom nanus, is just about one cm (half an inch) in length when fully grown, making it one of the smallest vertebrates.

In many true gobies, the pelvic fins have grown together into a suction cup they can use to hold on to substrate. Most have two dorsal fins, the first made up from spiny fin rays, while the other has some spines in the front followed by numerous soft rays.

They are most plentiful in the tropical and subtropical regions, but as a group are almost cosmopolitan in marine ecosystems. A few species tolerate brackish water, and some – Padogobius and Pomatoschistus species – even inhabit freshwater. They are generally benthic as adults (the spawn can distribute widely by ocean currents), only Sufflogobius bibarbatus is noted to be quite pelagic throughout its life. Most inhabit some sort of burrow or crevice and are somewhat territorial. In some cases, they live in symbioses with unrelated animals, such as crustaceans.

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Wikipedia