The Longjaw Mudsucker (Gillichthys mirabilis), or Gobio pardo in Spanish, uses a special “lung” to gulp oxygen from the air instead of the water. This allows it to stay alive if it is stuck onshore when the tide goes out. Inhabiting tidal mudflats, estuaries, and shallow sloughs, it can live out of water for six to eight days if kept moist. How? It absorbs oxygen from the air through veins in its mouth through a special membrane (a buccopharyngeal membrane). In contrast, most fish absorb oxygen by breathing through gills.
This fish feeds on algae, isopods (small crustaceans), amphipods (small crustaceans), and smaller fish. It is preyed upon by larger fish, egrets, herons, and humans, as sport-fishers use it as bait.
PHOTO CREDIT: Chris Mallory