Browsing by Subject "stygobites"

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The Mexican Blindcat Project: new discoveries and future efforts
(2017-03) Gluesenkamp, Andrew; Hendrickson, Dean A.; Sprouse, Peter
The endangered Mexican blindcat (Prietella phreatophila, Carranza 1954) is one of only four stygobitic ictalurid catfish in North America. Members of two monotypic genera (Satan eurystomus and Trogloglanis pattersoni) are known from the Edwards Aquifer in Texas and, until recently, Prietella (represented by P. lundbergi and P. phreatophila) was only known to occur in Mexico (northern Coahuila to southern Tamaulipas). The recent discovery of P. phreatophila in a cave on the Amistad National Recreation Area in Val Verde County, Texas is the result of decades of sporadic effort on both sides of the US/Mexican border and has stimulated a renewed effort to investigate the distribution, ecology, evolutionary history, and conservation status of this species. Collaborative efforts among The San Antonio Zoo, The University of Texas at Austin, Zara Environmental and The National Park Service are currently focused on habitat surveys in Texas as well as captive husbandry and propagation. Future efforts will include collaborators from the Comisión Nacional de Áreas Naturales Protegidas, Área de Protección de Recursos Naturales Sabinas, and the Laboratorio de Genética para la Conservación, Centro de Investigaciones Biológicas del Noroeste, La Paz to conduct expanded fieldwork in Mexico, hydrogeologic studies, and surveys using environmental DNA.
Satan’s Skeleton Revealed
(2017-07-15) Lundberg, John G.; Hendrickson, Dean A.; Luckenbill, Kyle; Arce H., Mariangeles
Satan eurystomus Hubbs & Bailey 1947, the widemouth blindcat, is endemic to the deep Edwards Aquifer below San Antonio, TX. Monotypic Satan is one of four subterranean ictalurids, Trogloglanis pattersoni, Prietella pheatophila and P. lundbergi, that all exhibit common features of stygomorphs: loss of eyes and pigmentation, hypertrophy of some chemo and mechanosensory systems, small size, and variously reduced musculoskeletal system. Each species is distinctive in its own ways, and hypotheses about their phylogenetic positions range from separate ancestries of each scattered among the lineages of epigean ictalurids to exclusive monophyly of a strictly subterranean clade. Specimens of Satan are rare, thus we used highresolution CT scans to develop the first detailed, richly illustrated descriptive and comparative study of its skeleton. Satan exhibits typical and singular reductive features plus complex structures, e.g. 3 novel symphyses closing the posterior cranial fontanel; an unusually deep temporal fossa; and an ornately shaped dorsal fin locking spinelet. Satan shares 15 synapomorphies with other ictalurid troglobites: the stygomorphisms plus bone and joint reductions. Satan shares 11 synapomorphies with Pylodictis, including increased numbers of cephalic sensory pores and paired fin rays, and several features associated with predatory suction feeding: wide gape, depressed head, expanded branchiostegal and opercular membranes and anterior extension of epaxial muscle. Incomplete character information, including lack of molecular data for Satan and Trogloglanis, poor quality of available skeletal preparations for Trogloglanis and Prietella, and uncertain identifications of some specimens of Prietella impede construction of a complete dataset for phylogenetic analysis.