Habitat: Occurs
in subterranean waters and is threatened by groundwater
pollution. Below the city of San Antonio Texas lies
a vast aquifer known as the Edwards (Balcones Fault
Zone) Aquifer. Two rare and unusual catfish reside
in the aquifer, Satan eurystomus, the widemouth
blindcat and Trogloganis
pattersoni the
toothless blindcat. They are the only known troglobitic
catfish in the United States. The only specimens of
both species ever collected have come from deep (1,200'
to 1,500') artesian wells within the city of San Antonio
itself and parts of southern Bexar County. The Balcones
Fault Zone is a complex system of limestone strata
(Edwards Limestone Formation) that has been fractured
and eroded over time by geological forces. Water travels
not only through numerous cracks and fissures but
also through massive underground caverns, streams
and rivers. The limestone strata slopes towards the
Gulf of Mexico. In northern Bexar County the limestone
formation is exposed on the surface. In the southern
part of the county the formation is 3,000 feet underground.
San Antonio's water supply comes from an area of the
aquifer known as San Antonio Pool and is considered
the "Good Water" zone. South of the Balcones
Fault Zone lies the Gulf Coastal Plain which contains
anaerobic, saline and sulfurous groundwater known
as the "Bad Water" zone. Water from both
zones meet and mix in a line that roughly parallels
Interstate Highway 35. Blindcats reside along this
narrow mixing zone and may be dependant on the unique
environment created at the mixing point of these two
zones. Etymolgy: The genus name Satan:
The prince of darkness. Hube liked to name cave fishes
with diabolic names based on the idea of hell being
underground. The specific name eurystomus:Wide-mouthed, from eurýs, wide or
broad, and stóma, mouth, referring to its wider
mouth compared with the sympatric Trogloglanis
pattersoni.
Common
Name:
Widemouth blindcat
Synonyms:
None
Family:
Ictaluridae
Distribution:
North America:
5 artesian wells penetrating San Antonio Pool of Edwards
Aquifer in and near San Antonio, Bexar County
in Texas, USA (29°30'N,98°30'W).
Size:
13.0cm. (5¼ins)
Temp:
-
p.H.
-
IUCN
Red List
This
species is listed as Vulnerable because it is represented
by only one or a few locations. Trend is unknown. The
species is vulnerable to groundwater depletion: if overpumping
of the aquifer occurs, this could drive the species
to Extinct or Critically Endangered in a short time
frame (needs updating IUCN 2014).
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