ABSTRACT
This chapter reviews current knowledge on the anatomy and physiology of cardiorespiratory systems of mudskippers, and suggests future research directions. The respiratory surfaces of mudskippers consist of the gills, the bucco-opercular cavity, and the skin. Most air-breathing fishes that live in hypoxic freshwater bodies throughout their life will not emerge on land, and will have specialized accessory respiratory organs; they are known as "aquatic air-breathing fishes". Mudskippers from the temperate zones overwinter in the mud for several months, during which they were reported to remain in water-filled burrows. The bucco-opercular cavity of mudskippers is especially enlarged and can accommodate a large volume of the ambient medium water or air within the cavity. The respiratory surface of the bucco-opercular cavity in mudskippers is perfused with systemic arterial blood. The respiratory surfaces of the skin are perfused with systemic arterial blood, as are the epithelia in the bucco-opercular cavity.
