Oxudercidae

Oxudercidae is a family of gobies made up of four subfamilies, Amblyopinae, Gobionellinae, Oxudercinae (which includes the mudskippers) and Sicydiinae, that were formerly classified under the family Gobiidae. It is sometimes called Gobionellidae, but the name Oxudercidae has priority. About 86 genera and around 600 species are recognised, with a cosmopolitan distribution in temperate and tropical areas, found in marine and freshwater environments and typically in inshore, euryhaline areas with silt and sand substrates. Many species live in fresh water, and some live on wet beaches and can stay out of water for days. The mudskippers move quickly over land and have eyes on top of the head on short stalks that they can raise or retract, seeing well out of water. One species, Gillichthys mirabilis, usually stays in water but gulps air when oxygen is low, holding it in its highly vascularised buccopharynx. Fossil oxudercids are known from the Middle Miocene of Europe.