Biology:Widemouth blindcat

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Short description: Species of fish

Widemouth blindcat
Satan eurystomus illustration 2.jpg

Critically Imperiled (NatureServe)[2]
Scientific classification edit
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Siluriformes
Family: Ictaluridae
Genus: Satan
C. L. Hubbs & R. M. Bailey, 1947
Species:
S. eurystomus
Binomial name
Satan eurystomus
C. L. Hubbs & R. M. Bailey, 1947

The widemouth blindcat (Satan eurystomus) is a species of North American freshwater catfish endemic to Texas in the United States. It is the only species in the genus Satan.

Description

It was first discovered inhabiting a well, and is adapted for a lightless underground environment. Like other cavefish, the widemouth blindcat lacks pigmentation and has no externally visible eyes. The eye remnants are extremely reduced in size with very little or no trace of a retina or lens; the optic tract is present, but always regresses before reaching the brain. The swim bladder in these fish is reduced, and the skull is mostly cartilaginous and not well-ossified, unlike the adults of most larger ictalurids. The lateral line is fragmentary and never reaches past the anterior part of the anal fin. This species also has a few paedomorphic traits (indicated by small size, kidney morphology, and weak ossification of the skeleton).[3] This species grows to about 13.7 cm (5.4 in) TL.[4]

Taxonomy

The widemouth blindcat's closest relative is the much larger flathead catfish (Pylodictis olivaris).[3]

Distribution and habitat

Along with the related toothless blindcat (Trogloglanis pattersoni), this species is distributed in five artesian wells penetrating the San Antonio Pool of the Edwards Aquifer in and near San Antonio, Texas.[4] These fish have been found with crustacean exoskeletons in their stomachs, and may be the top carnivore in their habitat.[3]

Conservation

The widemouth blindcat is a vulnerable species, and is threatened by groundwater pollution.[4]

See also

  • Blindness in animals

References

  1. NatureServe. (2014). "Satan eurystomus". IUCN Red List of Threatened Species 2014: e.T19917A19032828. doi:10.2305/IUCN.UK.2014-3.RLTS.T19917A19032828.en. https://www.iucnredlist.org/species/19917/19032828. Retrieved 16 December 2022. 
  2. "Satan eurystomus. NatureServe Explorer 2.0". https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.100902/Satan_eurystomus. 
  3. 3.0 3.1 3.2 Langecker, Thomas G.; Longley, Glenn (1993). "Morphological Adaptations of the Texas Blind Catfishes Trogloglanis pattersoni and Satan eurystomus (Siluriformes: Ictaluridae) to Their Underground Environment". Copeia (Copeia, Vol. 1993, No. 4) 1993 (4): 976–986. doi:10.2307/1447075. 
  4. 4.0 4.1 4.2 Froese, Rainer and Pauly, Daniel, eds. (2011). "Satan eurystomus" in FishBase. December 2011 version.

Wikidata ☰ Q3760645 entry