Toothless blindcat  (Trogloglanis pattersoni)

Classified as Vulnerable (VU) on the IUCN Red List 2007 (1).

This small, freshwater fish occupies underground waters in Texas, a habitat inaccessible to people, yet still vulnerable to the impacts of human activities. The pinkish-white toothless blindcat has a head that looks like that of a tadpole, and lacks both eyes and teeth (3) (4). The adipose fin, the fin on the back of the fish, is long, low and joined to the short and rounded tail fin (3).

Occurs only in the San Antonio Pool of the Edwards Aquifer, in and near San Antonio in Bexar County, Texas (4).

The toothless blindcat is a subterranean freshwater fish, inhabiting underground pools at depths of 305 to 582 meters (1) (5).

Due to the inaccessibility of its habitat, little is known about the toothless blindcat. Its sucker-like mouth and the mud-like contents of its stomach suggest that it feeds on fungal growths and detritus found amongst the soft bottom of the underground pool (5) (6). It is likely that is searches continuously and randomly for food on the bottom, without the need for effective sense organ to locate a meal (6). Olfaction, the sense of smell, appears to be the most effective sense the toothless blindcat possesses, which is possibly used to locate a potential mate (6).

As the toothless blindcat occurs only in one underground pool, any change in the pool environment could rapidly impact the entire population, making this species very vulnerable to extinction. The toothless blindcat inhabits water that is removed for human use (7), particularly for the enormous city of San Antonio. As San Antonio continues to grow at a rapid rate, ground water extraction will have an increasing impact on the blindcat’s habitat (8). In addition, as human populations rise, so does the probability of contamination of the Edwards Aquifer from agricultural and industrial runoff, such as fertilisers, pesticides and heavy metals (5) (7).

In addition to the World Conservation Union (IUCN) classifying the toothless blindcat as Vulnerable (1), the Texas Parks and Wildlife Department consider this species to be Threatened (9). Controls are placed on water extraction from the Edwards Aquifer by federal and state authorities, offering the toothless blindcat a little protection (8). However, to fully protect this little known species and the unique aquatic ecosystem it inhabits, further studies and long-term monitoring are required to inform conservation actions (8).

View information on this species at the UNEP World Conservation Monitoring Centre.

For further information on the toothless blindcat see:

• Florida Museum of Natural History:
  www.flmnh.ufl.edu/catfish/ictaluridae/toothlessblindcat.htm