The feeding responses of salamander larvae (Gyrinophilus porphyriticus) from caves in the Powell Valley in Virginia were investigated in the laboratory. The larvae locate prey by mechanoreception and capture the prey by a rapid sucking action, much like cave-limited salamanders do. Feeding success is greater with the isopod Asellus recurvatus (about 90 per cent) than with the amphipod Crangonyx antennatus (about 50 per cent), and this largely accounts for the higher frequency of A. recurvatus taken in choice experiments. G. porphyriticus readily ingested the unfamiliar isopod Lirceus usdagalun, but it took four weeks before it was digested as well. Small larvae tend to take small prey and large larvae take both large and small prey. Occasionally, larvae lunged at prey, which was usually unsuccessful. This behaviour seems to be a holdover from an evolutionary history in epigean environments where vision could be used to locate prey.
Culver, David C..
Feeding behavior of the salamander Gyrinophilus porphyriticus in caves.
International Journal of Speleology,
Available at: http://scholarcommons.usf.edu/ijs/vol5/iss3/14