Texas harbors 190 species of native freshwater fishes, 47% of which are considered imperiled. The primary cause of fish species imperilment in Texas is anthropogenic alteration of freshwater systems, which continues to occur at rates and scales that threaten the long-term resiliency of freshwater habitats, species, and ecosystems. Innovative conservation approaches are needed to restore and maintain functional watershed processes, restore freshwater habitats, and conserve native species, while simultaneously supporting human needs, such as flood control, municipal and agricultural water supply, water quality protection, and water-based recreation. The need for an integrated and holistic approach to conservation of freshwater systems has been the impetus for development of the Texas Native Fish Conservation Areas Network (Network). The Network consists of springs, ciénegas, creeks, rivers, and associated watersheds uniquely valued in preservation of Texas freshwater fish diversity. Twenty Native Fish Conservation Areas have been designated throughout the state. These were selected based on a spatial prioritization focused on identification of freshwater systems critically important to the long-term persistence of 90 freshwater fishes considered species of greatest conservation need. Through a shared vision of collaborative stewardship, conservation partnerships have formed among non-governmental organizations, universities, and state and federal agencies to plan and deliver actions within the Network to restore and preserve native fishes and their habitats. Furthermore, the Network has increased awareness of the ecological, recreational, and economic values of Texas freshwater systems, and helped increase interest and capacity of local landowners, communities, and recreational users (e.g., paddlers, anglers) to act as advocates and local stewards of these systems. By facilitating partnership development, coordinating broad-based conservation planning, and leveraging technical and financial resources toward strategic conservation investments, the Network has served as a catalyst for collaborative, science-based stewardship of native freshwater fishes and their habitats in Texas. The Network offers a successful case study in multispecies and watershed approaches to freshwater fish conservation transferrable to other states in the USA, with particular relevance to those states that, similar to Texas, consist predominately of privately-owned landscapes.

Aquatic biodiversity is threatened by human activities on a global scale. Mobile organisms such as stream fishes in particular are threatened by anthropogenic processes operating across jurisdictional and conservation area boundaries. Strategic conservation planning for broad, multi-¬species and multi¬jurisdictional landscapes benefits from datadriven approaches emphasizing persistence of priority species while accounting for human uses and stakeholder priorities. This study presents such an assessment for conservation of priority fishes of the Great Plains of the United States. Distribution models for 28 priority fishes were incorporated into a prioritization framework using the open-source software Zonation. A series of assessments were produced, including i) identification of distinct conservation areas based on connectivity and compositional similarity of priority streams, ii) perspectives for fish habitat condition prioritized towards undisturbed habitat (indicating protection potential) and disturbed habitat (indicating restoration potential), iii) ranking species conservation values at local (state) and global scales, and iv) development of 'bang-¬for-¬buck' perspectives emphasizing richness of species at state, basin, and study region scales. Assessment highlights include prioritizations primarily among unfragmented mainstem reaches, considerable state-boundary-based edge effects for rankings when using state-based conservation values, and identification of eight distinct regions containing natural communities of priority taxa. Further, we integrate an assessment product into a tiered framework for conservation implementation that facilitates coordination among stakeholders across jurisdictions and increases efficiency of conservation efforts. This set of analyses thus provides varying perspectives to direct diverse stakeholders in effective allocation of resources.

TAXONOMIC NOTES JUSTIFICATION Etheostoma segrex is a freshwater fish endemic to the headwaters of the Rio Salados de los Nadadores. While the historical distribution of this species may have included much of the headwaters of the Rio Salados de los Nadadores, extensive groundwater extraction, surface water diversion, and introduced Arundo populations have degraded much of the historical habitat, and it now only occurs in a few, localized areas within the Canyon below Cuatro Cienegas. Given the restricted distribution of this species and the plausible threat of extirpation due to habitat degradation resulting from continued groundwater extraction and surface water diversion, the entire population of E. segrex is considered as one location. Given a highly restricted extent of occurrence and area of occupancy, 1-5 locations, and inferred continuing decline in extent of occurrence, area of occupancy, and area, extent and/or quality of habitat, E. segrex is assessed as Critically Endangered. GEOGRAPHIC RANGE INFORMATION Etheostoma segrex is an endemic species from the headwaters of the Rio Salado de los Nadadores (Miller et al. 2005) which originates in the Sierra Madre Oriental and flows northeastward in central Coahuila, Mexico. Rio Salado is a tributary of Rio Bravo de Norte part of the Rio Grande system and crosses the Chihuahuan Desert of northern Mexico (Norris and Minckley 1997). POPULATION INFORMATION It is highly likely that populations of E. segrex have declined in recent years as a result of habitat loss due to water diversion and extraction, which has reduced the flow of the Rio Salado de los Nadadores by as much as 90% (Norris and Minckley 2002). In addition, introduced species may be impacting habitat quality in the area. Total population size is unknown. However, E. segrex has been relatively abundant in the few localities that still support populations (Norris and Minckley 1997, Norris and Minkley 2002). HABITAT AND ECOLOGY INFORMATION Etheostoma segrex is known to occur within freshwater rivers and streams, inhabiting riffles approximately 1.5-3 m wide and from 10 to 25 cm deep, of moderate turbulence over gravel and small cobble substrate (Norris and Minckley 1997). This species most likely feeds on small invertebrates and can be found mainly in vegetated, shallower areas, avoiding deeper, soft-bottomed eddies, pools or runs and turbulent ‘whitewater’ rapids (Norris and Minckley 1997). THREATS INFORMATION Both surface streams and underground waters in the Chihuahuan region are under increasingly heavy exploitation. Depletion of water resources is accelerating due to development for domestic, agricultural, and industrial uses. Etheostoma segrex is threatened by human water diversion and extraction through canals and wells, causing habitat alteration and degradation in water resources such as the Rio Salado de los Nadadores and its ground-water sources, which are under heavy demand in the very arid region of the eastern Chihuahuan desert (Norris and Minckley 1997). Significant darter habitat has already been severely degraded or lost and will not recover due to introduced Arundo populations. Recently, a number of wetlands and rivers in Cuatro Ciénegas, have also become infested with the invasive weed, Arundo donax, which may exacerbate water shortages (McGaugh et al. 2007). The most recent estimates of groundwater extraction around Cuatro Cienegas suggest that 55.4 million m3 are pumped annually from 101 well points, 93% of which are used in alfalfa cultivation to feed livestock (CONAGUA 2015). Large portions of habitat have recently been lost (e.g., Laguna Grande) resulting from declines in the water table (Felstead et al. 2015). Because the Comision Nacional del Agua does not have authority to restrict the future construction of wells, extraction is expected to continue into the immediate future (CONAGUA 2015). USE AND TRADE INFORMATION There is no information regarding the use or trade of E. segrex. CONSERVATION ACTIONS INFORMATION All aquatic systems of the Cuatro Cienegas basin have been designated as a Biosphere Reserve which may prevent further habitat degradation (Norris and Minckley 2002, IUCN and UEP 2018). However, the effects of this conservation action are unknown as the habitat of E. segrex does not extend into the protected areas. The American Fisheries Societies third compilation of imperiled freshwater and diadromous fishes of North America includes E. segrex as endangered under criteria 1 (present or threatened destruction, modification, or reduction of a taxon’s habitat or range) and 5 (a narrowly restricted range) (Jelks et al. 2008). However, these designations confer no protective benefit.

Established in 1964, the IUCN Red List of Threatened Species has evolved to become the world’s most comprehensive information source on the global conservation status of animal, fungi and plant species.

The Desert Fishes Council (DFC) is a non-profit (registered with the U.S. Internal Revenue Service in 1988) professional organization founded in 1969 with the mission of preserving "the biological integrity of desert aquatic ecosystems and their associated life forms, to hold symposia to report related research and management endeavors, and to effect rapid dissemination of information concerning activities of the Council and its members" (http://desertfishes.org). Fulfillment of that mission from the start included the production of a comprehensive report on all meeting activities (business meeting + abstracts of presented papers and posters) that was disseminated to the membership as the "Proceedings of the Desert Fishes Council". After 20 years of production and editing by Phil Pister, in 1990, Dean Hendrickson assumed editorship, producing the 1990-1994 volumes. Starting with the 1992 content, the editorial workflow changed from paper originals to all content being digital from abstract submission through published digital annual volumes available from the DFC website, and the Proceedings were formally registered as a serial publication (ISSN 1068-0381). Gary Garrett served as editor for the 1995-1996 volumes, and Hendrickson and Garret co-edited the 1997-1998 volumes. Hendrickson and Lloyd Findley served as co-editors for 1999-2007, adding Spanish translations of all abstracts. Following a decision by the Executive Committee to cease translation after the 2007 volume, Hendrickson continued as sole editor from 2008 to present. From the beginning, bound hard copies of the Proceedings were mailed to DFC members and a variable number of selected, mostly academic libraries, but around 2000, distribution switched exclusively to email and downloading from the internet. Eventually, all pre-1992 Proceedings issues were scanned to PDFs which were made available from the website, but, with conversion of the workflow to abstract submission direct to an online database in 2008, the classical content of the Proceedings became fragmented, with minutes of the meetings published each year on the website and a separate online abstracts database. Thus, even as the 50th anniversary of the DFC approached, the historical content of its Proceedings, though all available in digital format, remained scattered across many different files and formats, making comprehensive searching of the complete content laborious. At the time of finalizing this abstract (October 2018) and the compiled file here described, post-2007 abstracts of papers presented at the meetings were searchable from the website via the online abstract database, and the 1992-2007 PDFs of the annual Proceedings (all originally digital content) were separately searchable by downloading the annual files into PDF reader programs. The 1969-1991 volumes were also each searchable in the same way, but their textual (searchable) content, the product of automated Optical Character Recognition (OCR) done when that technology was still young, had many errors. Here, we provide the first single, text-based PDF file that brings the entire history of the DFC together in one place. The newer OCR technology used in this file produced much better results with the older content than what is found in the separate PDFs on the DFC website, and single searches of this file now extend across the complete history of DFC to present, greatly improving the utility of the archive for historical and scientific research. It is hoped that as more new content is appended, updates of this file will be produced, that remaining OCR errors (though less prevalent than in the early volumes) can eventually be corrected, and that the post-2007 meeting minutes lacking in this file can also be added, making this now permanently archived and openly available file a one-stop resource for the large corpus of historical and scientific conservation-related research built by the 4 editors authoring this archive, and by all of the members of the DFC who contributed content over the first half century of DFC's history.

Native Fish Conservation Areas of the southwestern USA consist of springs, ciénegas, creeks, rivers, and associated watersheds uniquely valued in preservation of freshwater fish diversity. These freshwater systems were identified through a spatial prioritization approach that identifies areas critically important to the long-term persistence of focal fish species. Through a shared mission of collaborative stewardship, conservation partnerships have formed among non-governmental organizations, universities, and state and federal agencies to plan and deliver actions to restore and preserve native freshwater fishes and aquatic habitats within the Native Fish Conservation Areas. Furthermore, the Native Fish Conservation Areas have increased awareness of the ecological, recreational, and economic values of freshwater systems in the region, and helped increase interest and capacity of local landowners, communities, and recreational users (e.g., paddlers, anglers) to act as advocates and local stewards of these systems. By facilitating partnership development, coordinating multi-species, watershed-based conservation planning, and leveraging technical and financial resources toward strategic conservation investments, Native Fish Conservation Areas have served as a catalyst for collaborative, science-based stewardship of native freshwater fishes and aquatic habitats in the southwestern USA. Efforts described herein to prioritize and deliver a network of Native Fish Conservation Areas in the southwestern USA offer a successful case study in multi-species and watershed approaches to freshwater fish conservation transferrable to other states and regions of the USA. This report offers a synthesis of recent (2011-2018) multi-species aquatic assessments, Native Fish Conservation Area prioritizations, conservation planning, and conservation delivery within the southwestern USA explicitly focused on implementation of the Native Fish Conservation Areas approach.

This database has roots in 4 previous compilations on ciénegas: 1) Hendrickson, Dean A., and W.L. Minckley. 1985. “Ciénegas - Vanishing Climax Communities of the American Southwest.” Desert Plants 6 (3): 131–75; 2) Minckley, T.A., D.S. Turner, and S.R. Weinstein. 2013. “The Relevance of Wetland Conservation in Arid Regions: A Re-Examination of Vanishing Communities in the American Southwest.” Journal of Arid Environments 88: 213–21. doi:http://dx.doi.org/10.1016/j.jaridenv.2012.09.001; 3) Minckley, Thomas A., Andrea Brunelle, and Dale Turner. 2013. “Paleoenvironmental Framework for Understanding the Development, Stability, and State-Changes of Ciénegas in the American Deserts.” In RMRS-P-67: Merging Science and Management in a Rapidly Changing World: Biodiversity and Management of the Madrean Archipelago III and 7th Conference on Research and Resource Management in the Southwestern Deserts; 2012 May 1-5; Tucson, AZ, edited by Gerald J. Gottfried, Ffolliott, Brooke S. Gebow, Lane G. Eskew, and Loa C. Collins, RMS-P-67:77–83. Rocky Mountain Research Station Proceedings. Fort Collins, Colorado: : U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. http://www.fs.fed.us/rm/pubs/rmrs\_p067.html; 4) Cole, A.T., and Cinda Cole. 2015. “An Overview of Aridland Ciénagas, with Proposals for Their Classification, Restoration, and Preservation.” In, Kathy Whiteman and William Norris (editors). Proceedings of the Fourth Natural History of the Gila Symposium, October 25–27, 2012. Western New Mexico University, Silver City, New Mexico. New Mexico Botanist Special Issue 4:28–56. http://gilasymposium.org/ and http://hdl.handle.net/2152/30285 (A static copy of the data from this paper is permanently archived, together with a copy of the complete paper, at http://hdl.handle.net/2152/30285, and the same static copy of the data are available in interactive (fusion table) format at https://www.google.com/fusiontables/DataSource?docid=1C6hbgWSgIPozfzO\_iFnefTERxp5rYoUAuT78XmYs). Now, this second fusion table-served database by Dean A. Hendrickson and Thomas A. Minckley implements the wishes of the Coles and Hendrickson as they began their collaboration. Here we combined the data from Cole and Cole (2015) and the data from Minckley et al 2013, as well as other data from our own knowledge bases and resources, and provide that content freely to the world (within constraints of the license on this fusion table) in this easily explored format. We are also implementing mechanisms to incorporate input of others to provide a dynamic, community-based, growing and constantly improving resource for the study and conservation of ciénegas. We hope that this database can now start to evolve and improve via contributions from a broader community of interested individuals. Since the initial compilation of Cole and Cole 2015 + Minckley at al 2013 (totaling 353 records), we have continued to sporadically add records as more information is provided to us (on Sept 13, 2018, record 366 was added). We hope to eventually add user-contributed photos and other improvements. In addition to data on occurrences and condition of ciénegas, we also have a shared, intermittently updated library of bibliographic metadata with links to publications (https://www.zotero.org/groups/north\_american\_cienegas). We invite users to contribute their bibliographic data, photos and pdfs to this collection, and to help us keep it, and this database, updated.

The primary aim of this grant was to work with Texas Parks and Wildlife (TPWD), Texas Advanced Computing Center (University of Texas at Austin), and other collaborators to (1) utilize Fishes of Texas Project (FoTX) data to aid in conservation of Texas fishes, (2) conduct field surveys in under-sampled areas of conservation interest, and (3) further develop the FoTX database and website as a research and management tool. While much of our work focused on Species of Greatest Conservation Need (SGCN), almost everything we did was applied to all species, or affected data for all species. This report documents how FoTX’s specimen-based data were used to produce species distribution models that, in turn, fed into prioritization analyses that led to official creation of Native Fish Conservation Areas (NFCAs) that are now becoming the foundation of aquatic resource conservation prioritization and management in Texas. Our data were also used by TPWD staff to update the Texas Natural Diversity Database, previously depauperate for fish data, and to develop state and global conservation rankings for fishes using NatureServe’s standard methodology. Using FoTX data, we also developed recommendations for updating TPWD’s SGCN list, which will inform conservation in Texas for many years. We also expanded the scope of FoTX beyond Texas, throughout entire drainages, thus reducing biases and analytical complications related to our previous political boundary that lacked a biogeographical basis. We also added many new records from new types of data sources, especially agency databases that complement the museum specimen data to provide a more thorough, updated and unbiased dataset for analyzing temporal and spatial trends in fish faunas. The FoTX website’s checklists were improved in many ways to increase their utility to resource managers, and the site also now accesses occurrence data held in formerly inaccessible, but now digitized and easily accessed documents. We used diverse resources and our occurrence data to determine native ranges for all Texas fishes, and now visualize them in our website's maps, so when viewed alongside occurrence data, users can more easily recognize and explore spatial and temporal trends. We focused another effort at understanding range changes through time, and produced dynamic graphs, that when fully implemented will update automatically as underlying data evolve, depicting and statistically describing locational and general range size changes through time. In addition to database and website work, we were also in the field alongside, and in close coordination with, TPWD staff, focusing on collecting areas previously lacking data, or where there were other conservation-related reasons for sampling. The resultant thousands of new specimens and tissue samples deposited and permanently housed in the University of Texas Biodiversity Collections now provide new, modern data points for ongoing conservation actions. In summary, this project allowed FoTX to continue to grow and diversify, moving away from focusing solely on archiving and improving the data to applying those data in diverse ways that maximize their value for conservation. The project also greatly increased collaborations between FoTX and TPWD staff, and inspired a Herps of Texas Project templated on the FoTX database schema and website, thus providing an efficient pathway for getting that project to a similar state, with the added advantage of a high level of inter-compatibility of most improvements across both sites. Our hope is that other projects, focusing on other taxa, continue to follow in our footsteps, allowing mutual benefit, and eventually query interfaces that provide users access to high quality data for entire ecological communities.

Desert ecosystems are particularly susceptible to anthropogenic influences. This is especially true for desert aquatic systems where limited water resources can be easily impaired by excessive water mining depleting the underlying aquifers. Although the aquatic environments and their associated native fishes are declining throughout the Chihuahuan Desert, we will focus on examples from the Big Bend region, the Balmorhea Springs Complex, the Pecos River region, and the Devils River region. Ongoing and impending land use and water consumption patterns suggest even further reductions in the near future. Even though numerous conservation activities are underway, archaic Texas water laws must be revisited and reformulated if the desert aquatic systems are to be truly conserved for more than the immediate future.

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.

The Widemouth Blindcat, Satan eurystomus Hubbs and Bailey 1947, was the second of four stygobitic species of Ictaluridae discovered in the subterranean waters of southern Texas and northeastern Mexico. The skeletal anatomy of Satan has been scarcely known from a few, dated radiographs. Using additional radiographs and high resolution CT-datasets for two well-ossified specimens, we applied high-resolution X-ray computed tomography (HRXCT) to visualize, illustrate and describe the bony skeleton of Satan. We also provide an online archive of still and animated tomographic images of the skeletal anatomy of this little-known species. The skeleton and soft anatomy of Satan are distinctive. Twelve skeletal autapomorphies are described that singularly distinguish Satan within Ictaluridae and, probably in combination, from all other catfishes. Some of these are reductive losses or simplifications of skull bones (e.g. loss of one infraorbital bone; reduced ornamentation of the pterotic bone) and joint complexity (e.g. simple overlapping frontal-lateral ethmoid articulation; loosely ligamentous interopercle-posterior ceratohyal joint). Some of the autapomorphies are anatomically and perhaps developmentally complex (e.g. a novel series of three midline joints closing a middle span of the posterior cranial fontanel; a deeply excavated temporal fossa and an unusually enlarged interhyal bone). The tiny dorsal-fin spinelet (first lepidotrich) of Satan has a novel peaked and twisted shape. Ten apparent and exclusive synapomorphies within Ictaluridae gathered from this and previous studies suggest that Satan and Pylodictis are closest relatives. Most of these are functionally related to prey detection and suction feeding: fusion of the symphyseal mandibular sensory pores and increase in the number of preoperculo-mandibular canal pores; depressed, flattened heads and wide transverse mouths; prominent posterior process of the lateral ethmoid alongside and below the frontal bone margin; vertical and blade-like supraoccipital posterior process; unique arrangement of the parasagittal and occipital muscleattachment crests on the skull roof; large triangular panel of integument within the operculum framed by the opercle, preopercle and interopercle bones; elongated posterior ceratohyal; and, form of the fourth supraneural and loss of its anterior nuchal plate. In contrast, 15 synapomorphies recovered by Arce-H. et al. 2016, are confirmed suggesting that Satan is one of the four stygobitic ictalurids comprising a “Troglobites” subclade within the family: (Trogloglanis, Satan, Prietella phreatophila, P. lundbergi). These features include three stygomorphic and reductive apomorphies that are exclusive within Ictaluridae: loss of fully developed eyes and pigmentation, and simplification of the fifth vertebra and its joint with the Weberian apparatus. Twelve other synapomorphies shown by the Troglobites are also apparent homoplasies of character states shared with various other ictalurids. These include reductive characters such as shortened lateral line canal, reduced infraorbitals and underdeveloped or incomplete ossifications of the pterotic, supraoccipital, hyoid arch bones and transcapular ligament. Also, the Troglobites and various other ictalurids have: an adnate adiposecaudal fin, foreshortened anterior cranial fontanelle, reduced ventral wings of the frontal bone, replacement of bone by cartilage in hypohyal joints; incompletely ossified transcapular ligament, and consolidation of some hypural bones. Completing a full morphological character dataset across the Troglobites has been impeded by incomplete specimen preparations and study of P. lundbergi and to a lesser extent, P. phreatophila and Trogloglanis.

The Widemouth Blindcat, Satan eurystomus Hubbs and Bailey 1947, was the second of four stygobitic species of Ictaluridae discovered in the subterranean waters of southern Texas and northeastern Mexico. The skeletal anatomy of Satan has been scarcely known from a few, dated radiographs. Using additional radiographs and high resolution CT-datasets for two well-ossified specimens, we applied high-resolution X-ray computed tomography (HRXCT) to visualize, illustrate and describe the bony skeleton of Satan. We also provide an online archive of still and animated tomographic images of the skeletal anatomy of this little-known species. The skeleton and soft anatomy of Satan are distinctive. Twelve skeletal autapomorphies are described that singularly distinguish Satan within Ictaluridae and, probably in combination, from all other catfishes. Some of these are reductive losses or simplifications of skull bones (e.g. loss of one infraorbital bone; reduced ornamentation of the pterotic bone) and joint complexity (e.g. simple overlapping frontal-lateral ethmoid articulation; loosely ligamentous interopercle-posterior ceratohyal joint). Some of the autapomorphies are anatomically and perhaps developmentally complex (e.g. a novel series of three midline joints closing a middle span of the posterior cranial fontanel; a deeply excavated temporal fossa and an unusually enlarged interhyal bone). The tiny dorsal-fin spinelet (first lepidotrich) of Satan has a novel peaked and twisted shape. Ten apparent and exclusive synapomorphies within Ictaluridae gathered from this and previous studies suggest that Satan and Pylodictis are closest relatives. Most of these are functionally related to prey detection and suction feeding: fusion of the symphyseal mandibular sensory pores and increase in the number of preoperculo-mandibular canal pores; depressed, flattened heads and wide transverse mouths; prominent posterior process of the lateral ethmoid alongside and below the frontal bone margin; vertical and blade-like supraoccipital posterior process; unique arrangement of the parasagittal and occipital muscle-attachment crests on the skull roof; large triangular panel of integument within the operculum framed by the opercle, preopercle and interopercle bones; elongated posterior ceratohyal; and, form of the fourth supraneural and loss of its anterior nuchal plate. In contrast, fifteen synapomorphies recovered by Arce-H. et al. 2016, are confirmed suggesting that Satan is one of the four stygobitic ictalurids comprising a “Troglobites” subclade within the family: (Trogloglanis, Satan, Prietella phreatophila, P. lundbergi). These features include three stygomorphic and reduction apomorphies that are exclusive within Ictaluridae: loss of fully developed eyes and pigmentation, and simplification of the fifth vertebra and its joint with the Weberian apparatus. Twelve other synapomorphies shown by the Troglobites are also apparent homoplasies of character states shared with various other ictalurids. These include reductive characters such as shortened lateral line canal, reduced infraorbitals and underdeveloped or incomplete ossifications of the pterotic, supraoccipital, hyoid arch bones and transcapular ligament. Also, the Troglobites and various other ictalurids have: an adnate adipose-caudal fin, foreshortened anterior cranial fontanelle, reduced ventral wings of the frontal bone, replacement of bone by cartilage in hypohyal joints; incompletely ossified transcapular ligament, and consolidation of some hypural bones. Completing a full morphological character dataset across the Troglobites has been impeded by incomplete specimen preparations and study of P. lundbergi and to a lesser extent, P. phreatophila and Trogloglanis.

While the Yaqui Catfish, Ictalurus pricei, has a long history of listing and conservation interest, the still undescribed Chihuahua Catfish remains largely unknown to many working on fishes and aquatic resource management in its range. Like Yaqui Catfish, it is similar to the ubiquitous Channel Catfish, and until awareness is increased, it will remain understudied and with little protection. Also like Yaqui Catfish, hybridization with closely related species greatly confounds research and recovery efforts. Known only from an unfinished manuscript describing it, and many specimens identified cryptically (since it remains undescribed) as this species in a few collections' databases, and occasional mentions in the literature, its historic distribution includes most of the Rio Grande/Bravo watershed (including all 3 major sub-basins (Conchos, Pecos, Grande/Bravo) and a relatively small area of the Gila River basin. It appears to be now very rare, and it appears to hybridize with both I. punctatus and I. lupus. Cytochrome b sequences obtained from one recently collected specimen from each the Gila basin and the Conchos basin in Chihuahua (at or very near the manuscript's type locality), indicate two divergent haplotypes. The manuscript's authors did not recognize that divergence, and considered it introduced in the Gila, so did not include specimens from there in their morphological analysis, but thought the form there to be introduced from the Río Grande/Pecos. We'll here present images of specimens, and summarize the diagnostic characters known from the manuscript, though hybridization clearly confounds morphological diagnosis. All those collecting catfishes anywhere in the species' broad range are asked to be aware of its existence, and to deposit large series of vouchers and tissues in museum collections for future efforts to better diagnose these rare fishes and conserve them.

Trout, salmon, grayling and whitefishes (Salmonidae) are among the most ecologically and economically important fishes. They also are among the most vulnerable to global warming, and increasing drought, floods, and wildfires. In North America, salmonids occur from central Mexico northward along coastal regions and mountainous interiors to the Arctic Plains. A variety of existing stressors have reduced population sizes and extent and fragmented habitats, making salmonid populations increasingly vulnerable to climate-driven disturbances. This contribution explores specific threats posed by climate change and suggests actions that can help these coldwater-dependent species adapt to an increasingly warm and uncertain future.

Discovery of the Mexican blindcat, Prietella phreatophila, in Texas in 2016 generated interest in the species, which had previously only been known from Mexico but is listed as a foreign endangered species in the US. Consequently, an effort was undertaken to conduct a conservation status assessment of the fish using standardized methods developed by NatureServe. These assessments aim to determine the extinction risk of species and produce conservation ranks, which can be used to inform listing statuses and policy decisions and to determine conservation priorities. The rank is determined by assessing factors in three main categories: rarity, threats, and trends. Here we used three rarity and one threat factor in the NatureServe rank calculator to determine the global conservation rank of P. phreatophila. Known occurrences were compiled, and the online tool GeoCAT (geospatial conservation assessment tool) was used to determine range extent and area of occupancy. Number of occurrences (e.g., populations) was estimated based on the spatial distribution of observations and their proximity to one another. Threat comprised scope, which was assessed in ArcGIS by intersecting the total area covered by a given threat with the known occurrence area of P. phreatophila, and severity, which was estimated based on expert opinion. The resulting conservation rank was G2 (globally imperiled; roughly equivalent to IUCN’s Vulnerable rank); however, complete data were not available for any factor thus motivating the need for further study. When new data are available, the rank can be easily updated with this new information using the rank calculator.

Mexican blindcat, Prietella phreatophila, described in 1954 from a cave system near the town of Múzquiz in central Coahuila state, and considered a Mexican endemic, was listed by the U.S. Fish and Wildlife Service as a foreign endangered species (protected "wherever found") in 1970. Explorations in the 1990s discovered many new localities extending nearly to the international border, and in 2016 the species was discovered in Amistad National Recreation Area (ANRA) in Texas, just north of the international border near Del Rio. Not only does the discovery support the aquifer of this fish being an internationally shared resource, but the stygobitic invertebrate biota found with the fish indicates a potentially large extent of the aquifer, and thus possibly the fish, in Texas. Invertebrate faunal connections (historic or current) extend from the Amistad Lake area of the new occurrence west into the Trans-Pecos region and east into the Edwards Aquifer of central Texas. We explore implications of this for both water management and evolutionary history of this and other blind ictalurids, and suggest that population genetic studies of both stygobitic fishes and invertebrates could help hydrogeologists better define often difficult to map aquifer extents and interconnections. While NPS is continuing to support the cave explorations of ANRA that produced the Texas discovery, we propose a broader bi-national sampling effort for both the fish and invertebrates extending well beyond the current known distribution of P. phreatophila. We also pointed out questions about phylogenetic relatedness of P. phreatophila and P. lundbergi further south, as well as the possibility of a monophyletic clade of blindcats, including those of the Edwards Aquifer, Satan and Trogloglanis. If substantiated, that evolutionary history would imply broader historic inter-aquifer connections ranging from the San Antonio area as far south as southernmost Tamaulipas. Finally, we report establishment of a small captive population of Prietella phreatophila at San Antonio Zoo for research and possibly eventual conservation applications.

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.

This presentation reviews the current status of knowledge about the American Eel, its conservation status and distribution in Texas, and work in progress to learn more about the species in Texas.