Burrowing, Emergence, Behavior, and Functional Morphology of the Australian Salamanderfish, Lepidogalaxias salamandroides

Abstract

The salamanderfish is a small endemic salmoniform that inhabits acidic, ephemeral freshwater in southwestern Australia. This paper documents that L. salamandroides burrows into damp sand to avoid the desiccation of its habitat and that it can emerge after an overnight rainfall of 8 mm. When dry pools were flooded by the release of water from a fire truck, fish were caught within 10 minutes. In captivity, the salamanderfish was observed to bend its head at right angles to the body. This is possible because of the wide gaps between the skull and first vertebra and between adjacent vertebrae. Reduced ribs also result in a very flexible body. These features and the robust, wedge-shaped skull are probably adaptations to burrowing. Scanning electron microscopy revealed cycloid scales and a formidable dentition.