TAXONOMIC NOTES Undescribed species. Affinity appears to be with Mexican golden trout in the adjacent Fuerte basin, but genetic work shows this trout to be unique. Nathaniel Thomas Lupton collected two specimens of trout from this region in 1884 (Cope, 1886), but the location of the specimens and the collection locality remain a mystery. JUSTIFICATION This species is known only from about 2 km of the Arroyo del Molino and a tiny headwater tributary in the Río Porvenir sub-basin of the southern Río Conchos watershed. While there are currently no major threats affecting this species or its known habitat, total population size is unlikely to exceed 250 individuals. Therefore, it is assessed as Endangered (EN) under criterion D. More rigorous sampling in adjacent areas is needed to determine if additional populations exist. GEOGRAPHIC RANGE INFORMATION This species is currently known only from about 2 km of the Arroyo del Molino and a tiny headwater tributary in the Río Porvenir sub-basin of the southern Río Conchos watershed, which occurs at an elevation between 2,300-2,350 m asl. Therefore, extent of occurrence (EOO) and area of occupancy (AOO) are both estimated at 2 km². Localized threats are expected to affect the entire known range of this species. Area of Occupancy and EOO are currently stable, given the single location is highly isolated and free of major threats. POPULATION INFORMATION Total population size is unknown. However, given a highly restricted range, habitat specificity for cold headwater streams, and preliminary population surveys in 2007, population size is inferred to be between 100-250, and unlikely to exceed 1,000. Population trend is suspected to be stable, given the lack of major pervasive threats, and no evidence of habitat decline. The current known population is not considered to be severely fragmented. However, if additional subpopulations exist, genetic exchange between subpopulations is likely severely restricted given an inability to disperse through thermal barriers in river mainstems. HABITAT AND ECOLOGY INFORMATION This species is restricted to one headwater stream of the Río Porvenir sub-basin in the Conchos watershed. Cold and clear water is required. Nothing is known of the behavior, life cycle, or growth patterns of this species. THREATS INFORMATION There appear to be no immediate threats to the existing population, as it is remote and not easily accessible. Limitations to range expansion include overgrazing by livestock and the effects of logging and road building in this sub-basin. Future genetic introgression with rainbow trout is expected, given government initiatives that promote the development of hatcheries within the region. USE AND TRADE INFORMATION There is no known trade in this taxon. CONSERVATION ACTIONS INFORMATION There are no species-specific conservation actions in place. Recommended conservation actions include education of the local peoples regarding conservation status and efforts to keep livestock out of the lower reaches of the arroyo. There appears to be minimal impact in the species' actual habitat. More rigorous sampling to identify additional subpopulations of the species is recommended, given the area is remote and difficult to survey. Additionally, more detailed information regarding population size, population trend, and life history and ecology would be useful in guiding future conservation action.

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 through 2019. 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 2019) and final compilation of this volume, 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 (from the DFC website) 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. Some business meeting minutes since 2007 were available via the DFC website, but were difficult to find there, and many were missing. Here, we provide the first single, text-based PDF file that brings the entire history of the DFC together in one place. All 2008-2018 business meeting minutes have been found and added to this file. The newer OCR technology used in this file produced much better results with the older, graphic-based content than what is found in the separate PDFs on the DFC website, and this single compilation file will now allow easy text-based querying across the complete history of DFC to present, greatly improving the utility of the archive for historical and scientific research. We are happy to now provide this permanently archived, and openly available file as a one-stop resource for access to the large corpus of historical and scientifically important conservation-related research built by the four editors who compiled this archive, and by all of the members of the DFC who contributed content over the first half century of DFC's history. As we now turn management of DFC’s future content over to future Proceedings Editors, we suggest that they initiate work (perhaps Citizen Science-based?) to correct the remaining OCR and other errors (though less prevalent than in the early volumes), and ideally eventually more fully parse, and continue mining of, the contents to serve it via a digital, online database in compliance with standard bibliographic, taxonomic, and geo-spatial data standards, comparable to the way other modern scientifically useful content is served and linked across the Internet. Ideally, authors’ presentations could also be linked-in from permanent archives (such as DFC’s F1000 channel).

American theatergoers are familiar with director John Huston’s classic movie of 1948, The Treasure of the Sierra Madre, based on a novel written by B. Traven and starring Humphrey Bogart as Fred C. Dobbs. At least north of the border, Traven’s tale of loco gringos prospecting for gold made Mexico’s rugged mountains famous, and many cinephiles still recognize the famous quote by Gold Hat the bandito: “Badges! We ain’t got no badges. We don’t need no badges! I don’t have to show you any stinking badges.” Huston filmed most of his mountain scenes on location in Mexico, and some 50 years later, we found ourselves in the Sierra Madre Occidental (henceforth, SMO) of northwest Mexico with our own saga of prospecting for “gold” beginning to unfold. Always without badges but often stinking after days of back-country camping and hiking, our binational and otherwise diverse cast of academic, government, and nonprofit biologists and fly fishers came to call itself Truchas Mexicanas (Mexican trout), after the different, but also gilded, treasure we were chasing.

Two Mexican trout taxa are formally described (Oncorhynchus chrysogaster, and O. mykiss nelsoni), but many other congeners have long been informally recognized as likely distinct. For more than two decades, the binational Truchas Mexicanas team searched for and collected trout broadly throughout the Sierra Madre Occidental of Sonora, Chihuahua, Sinaloa and Durango. That fieldwork documented that the native range of the genus extends to the Tropic of Cancer, or \textasciitilde1000 km S of El Paso, Texas, and indicates that most of Mexico's trout exist as small, isolated populations with very restricted ranges. Genetic studies of Truchas Mexicana's specimens demonstrated that the many distinctive lineages found in Mexico are at least as divergent from one another as are their much more thoroughly-studied relatives in the O. mykiss complex in the Western U.S.A. When an opportunity presented itself to list the many still undescribed Mexican forms in the IUCN Red List, as part of a large project to assess the conservation status of the entire Mexican freshwater fish fauna, the authors rapidly compiled the necessary documentation and submitted the required proposal. Once the proposal was accepted, we then worked with IUCN staff to finalize formal conservation assessments that should be published in the Red List about 1 month after this presentation is given at the 2019 meeting. We hope that this official listing of these 12 mostly undescribed Mexican endemic species, with 3 determined to be Critically Endangered (CR), 5 Endangered (EN), 3 Near Threatened (NT), and one Data Deficient (DD), will call attention to this important biodiversity asset and open doors for much-needed financial support for the conservation actions that are so desperately needed. Meanwhile, work continues on the morphologically difficult diagnoses of the new species and their descriptions.

Natural history specimen data collected and/or identified by Hendrickson, Dean A., https://orcid.org/0000-0001-7835-0295. Claims were made on Bloodhound, https://bloodhound-tracker.net using specimen data from the Global Biodiversity Information Facility, https://gbif.org. This is a continual growing compilation as new specimens are cataloged, published by the repositories in which they are held, and attributed to the author via Bloodhound.

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.