Northern cavefish

Northern cavefish
Conservation status
Vulnerable (IUCN 2.3)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Percopsiformes
Family:	Amblyopsidae
Genus:	Amblyopsis
Species:	A. spelaea
Binomial name
Amblyopsis spelaea (DeKay, 1842)

Amblyopsis spelaea, The northern cavefish, northern blindfish, or blind cavefish of the mammoth cave is found in caves through Kentucky and southern Indiana. It is listed as a threatened species in the United States and the IUCN lists the species as vulnerable, with a range of about a dozen cave streams.

The White River, flowing east to west south of Bedford, Indiana, delimits the northern range of Amblyopsis spelaea. These fish are not found in caves north of the White River. According to the "Guide to America", describing the famous Mammoth Cave, located in the National Park of the same name in Kentucky: "The mammoth cavern consists of many huge caves and underground galleries, arranged over five floors, with a total length of one hundred and fifty miles. The runner wider measures two hundred feet long, the most impressive cave a hundred high and the well depths, a hundred and fifty. The Echo River, three-quarters of a mile long and two hundred feet at most, wide, slides under a dome of fifteen high. owes its name to the endless echoes repeats. Its waters are having fishes without eyes. "

The fishes referred to are the most typical ambliopsidos spelaeus species, known to science since 1842. In just over ten inches long, have very slender body, long head, no eyes and scales, and equipped, as all the tops and sides of the trunk, numerous transverse linear reliefs, in which sensory endings abound. The dorsal fin, well behind, is very high, short, and is at the same level as the anal, which is the same dimensions. The tail is rounded little fan later, the pectoral fins have medium development, and abdominal, located in the middle of the body, are very small. Depigmented and translucent, its pinkish color is due to the hemoglobin in its blood. Abundant in the famous Mammoth Cave, being a distraction for visitors. Calmly swim near the surface "as white aquatic ghosts" in the words of Professor Cope, who studied in the late nineteenth century, ready to disappear into the depths to sound. These fish, barely sensitive to light, they perceive the slightest vibrations in the air and take refuge in the murky river's depth. They eat many animals, almost all blind or low vision, with white color of the cave fauna who live in the same medium. Despite its apparent fragility, amblyopsis enjoy a tenacious vitality and can be kept in aquariums. J.R.R. Tolkien, in his book "The Hobbit" describes fish like these inhabitants of an underground lake.

The blind cavefish is blind and depigmented. Despite the lack of eyes, it does respond to light and moves away from it (scotophilia). Cavefishes are generally small, ranging up to 11 centimetres (4.3 in) in length. Most do not have pelvic fins, although Amblyopsis spelaea has small ones with up to six rays. They are predator just only resulting from the lack of vegetation, inhabiting subterranean water or caves which have consolidated mud-rock substrates in shoals and silt-sand substrates in pools but is more often found in caves with uniform silt-sand substrates. Has low reproduction rate and broods eggs in gill cavity for up to 4-5 months. Can live for 2 years without food because of low metabolic rate.

Other animals which inhabit the Mammoth Cave National Park include: two genera of Crickets (Hadenoecus subterraneus) and (Ceuthophilus stygius) (Ceuthophilus latens), a Cave salamander (Eurycea lucifuga), two genera of eyeless Cave Fish (Typhlichthys subterraneus) and (Amblyopsis spelaea), a Cave Crayfish (Orconectes pellucidus), and a Cave Shrimp (Palaemonias ganteri). In addition, some surface animals may take refuge in the entrances of the caves but do not generally venture into the deep portions of the cavern system.

References

• Froese, Rainer, and Daniel Pauly, eds. (2005). "Amblyopsis spelaea" in FishBase. 10 2005 version.