More Adaptive Comparisons of Cave Animals

Ozark Fish

Axolotl

To pursue our study on adaptive comparisons of cave animals, started with 27 bugs discovered recently and continued with organisms known since 1966, we will see now some salamanders living inside the caves:

Found at: http://www.geocities.ws/kubyimm3/axol.gif [Thank you for saving it!]

Left: Several highly adapted species of cave salamanders found in Texas probably looked somewhat like this common surface dweller before they entered caves. Like its cave-dweling relatives, this salamander retains feathery gills and other larval characteristics even as an adult. Right: Two Texas salamanders, each inhabiting separate cave systems, probably resemble past stages of the highly adapted Eurycea rathbuni. Compared with their surface relative, they show progressively greater loss of pigment, degeneration of eyes, elongation of legs, slimming of the body, and flattening of the snout. Possibly at some time in the future both species also will develop the grotesque modifications of Eurycea rathbuni.
Eurycea rathbuni (Stejneger, 1896) Texas Blind Salamander.

With some similarities to Eurycea rathbuni, Typhlomolge rathbuni, the famous Texas blind salamander, which inhabits the San Marcos Pool of the Edwards Aquifer. This was the first organisms listed as endangered in the USA in 1967.
And similar to the second one: Eurycea, a troglobitic salamander from the Buttercup Creek Karst, near Austin, Texas.

Found at: http://www.geocities.ws/kubyimm3/ozark.gif [Thanks for saving it!]

Left: Slender and ghostly pale, the fully transformed adult Ozark blind salamander is three to four inches long. Its gills have disappeared, and its eyelids have grown together over small, nonfunctional eyes. The adult salamander moves freely in and out of water and usually lives deeper in caves that the larval form (right), which is from two to three-inch-long, and lives in cave streams and pools but sometimes ventures aboveground, unlike the adult, it has eyes, conspicuous coloration, and plumelike gills. Right: As the larval Ozark blind salamander approaches metamorphosis, it gradually loses pigmentation, its gills begin to regress, and its eyes become smaller in proportion to its head. Already losing the use of its eyes, the maturing larva begins to depend more on vibrations sensed through its lateral line system in order to locate isopods (in the picture), flatworms, and other small prey.

Head of G. palleucus, the Tennessee cave salamander. There are three subspecies.

References:
Mohr, Charles E. & Poulson, Thomas L., 1966, Our living world of nature: “The Life of the Cave”, McGraw-Hill, the World Book Encyclopedia and the U. S. Department of the Interior, 232 p., New York.

Alphabetical List of Cave Life.

Other cave-dwellers:

http://fdocc.blogspot.com/2006/02/adaptations-of-cave-fish.html

http://fdocc.blogspot.com/2006/01/new-27-cave-bugs.html

http://fdocc.blogspot.com/2006/01/laupala-cricket-variation.html

http://fdocc.blogspot.com/2006/02/cave-dwellers-known-since-1966.html