Mexican Blindcat

Prietella phreatophila

Description

The Mexican blindcat is a small catfish, achieving a length of up to 0.5 in (1.2 cm). Its eyes are greatly reduced and non-functional, and its skin lacks pigmentation.

Behavior

The Mexican blindcat does not have functional eyes, and perceives its environment through its tactile barbels and probably also by sensing electrical fields. The male digs a shallow nest, where the female lays eggs, which are fertilized externally by milt (sperm) excreted by the male. The developing eggs in the nest are guarded until they hatch. The Mexican blindcat has been maintained in captivity, but it has not been induced to breed.

Habitat

The Mexican blindcat occurs in dark, underground, freshwater pools and wells in tropical areas. This unusual aquatic habitat is known as "hypogeous," or underground habitat. The underground habitat is periodically subject to rapid changes in water volume, due to flows associated with surface rains and underground streams passing through bedrock fractures.

Distribution

The Mexican blindcat was first discovered in underground cave-pools and wells in central Coahuila State, Mexico. Recent discoveries of populations of congeneric (same genus) blindcats in northern and eastern Mexico have expanded the range of this fish. Initial taxonomic research considers that these populations represent at least two different species.

Threats

Some populations of the Mexican blindcat have been severely affected by habitat damage caused by pollution by nutrients and pesticides, and perhaps by excessive collecting.

Conservation and Recovery

Recent fieldwork in northern Mexico has found additional populations of the Mexican blindcat, so the species may not be as endangered as once thought. However, all of its known habitats are vulnerable to pollution and disturbance. The habitats of the Mexican blindcat are not protected.

Contact

Instituto Nacional de Ecología
Av. Revolución, 1425
Col. Campestre, C.P. 01040, Mexico, D.F.
http://www.ine.gob.mx/

References

Borowsky, R. 1996. "The sierra de El Abra of northeastern Mexico: blind fish in the world's largest cave system." Tropical Fish Hobbyist 44(7): 178-188

Parzefall, J. 1993. "Behavioural ecology of cave-dwelling fishes." In Behaviour of Teleost Fishes, edited by T. J. Pitcher. Chapman & Hall, London. pp. 573-606.