Documentation Related to a 1991 Observation of Sturgeon in the Rio Grande – Río Bravo, USA (Texas) and Mexico (Coahuila)

This digital archive provides a compilation of previously unpublished information regarding a 1991 observation of a live sturgeon (Family Acipenseridae) in the Rio Grande-Río Bravo of the USA and Mexico. Though a few specimens collected in the 19th century support occurrence of sturgeon in this river basin, lack of credible, recent records has often led to this species not being recognized as part of the basin’s native fish fauna, and certainly not part of its modern fish community. The second and third authors of this document manage the Fishes of Texas Project (Hendrickson, Dean A., & Cohen, Adam E. (2015). Fishes of Texas Project Database (version 2.0). Texas Advanced Computing Center, University of Texas at Austin. http://doi.org/10.17603/C3WC70) and knew of the unpublished 1991 observation of sturgeon reported here. They requested the content provided here from first author (Platania) who provided what follows below (verbatim as received in April 2018) and permission to archive it for public access.Integrative Biolog

Year 1 report for ‘Conserving Texas Biodiversity: Status, Trends, and Conservation Planning for Fishes of Greatest Conservation Need’

State Wildlife Grant Program, grant TX T-106-1 (CFDA# 15.634), Contract No. 459125 UTA14-001402Substantive progress was made on all major Project Activities in this first year: Activity 1. Coordinate and Facilitate Science and Conservation Actions for Conserving Texas Biodiversity - We expanded and strengthened UT-TPWD coordination, transitioning the relationship between these partners into a much more collaborative one than was previously realized. The flow of data between TPWD and the Fishes of Texas Project (supported in part by this project) has become much more bi-directional. Many newly collected TPWD specimens, agency databases, legacy data products and reports, and feedback from resource managers are now beginning to contribute substantively to growth and diversity (now including non-specimen-vouchered records) of data served through the FoTX Project’s websites. Work on cleaning and normalizing of FoTX’s online specimen-vouchered database continued, and the updated FoTX occurrence and distribution data are being actively used. Most recently they were used by this project, together with expert (TPWD, UT and others’) opinions, to develop recommendations on conservation status of native fishes of Texas’ Species of Greatest Conservation Need for TPWD’s consideration in anticipated updates to the Texas Conservation Action Plan. Within two months of this report, a new and substantially larger and improved version of the FoTX website/database and related collection of images, field notes, and ancillary datasets, will be formally announced. Activity 2. Identify Priority Geographic Management Units for Conserving Fishes of Greatest Conservation Need - We used FoTX data in a systematic conservation area prioritization analysis to identify Native Fish Conservation Areas (NFCAs) for large portions of Texas where such comprehensive planning had not been previously carried out. Updated and new FoTX data for all Texas fish Species of Greatest Conservation Need (SGCN) were used in production of newly improved Species Distribution Models for input into this planning process, and the results of the planning exercise have already been integrated by TPWD into management prioritizations of both those species and the resultant NFCAs. Activity 3. Develop Monitoring and Conservation Plans for Native Fish Conservation Areas - Monitoring and conservation plans were delivered to TPWD for all NFCAs identified in Activity 2. Activity 4. Conduct Field-Based Surveys Detailed Biodiversity Assessments (i.e. Bioblitzing), and Citizen-Based Monitoring - Field surveys with detailed biodiversity assessments (“bioblitzes”) and citizen-based monitoring were conducted in three areas selected collaboratively by TPWD and FoTX Project staff from within the identified NFCAs: Nueces River headwaters, Big Cypress Bayou basin, and Village Creek basin. Along with this field effort, FoTX Project staff developed and circulated guidelines and best practices, and provided training for citizen-based monitoring that leverages iNaturalist for capture and reporting of photo-vouchered occurrence records in ways that will help assure scientifically useful data are obtained. All specimens acquired during these field efforts, and from many other routine specimen acquisitions from across the state (1845 total records/jars of specimens), were cataloged in the UT Fish Collection database. From there, these new records will soon be fed into GBIF, VertNet, FishNet2 and other major online data aggregators, including the online Fishes of Texas database.Texas Parks and Wildlife Department; U.S. Fish and Wildlife ServiceIntegrative Biolog

The 2.4-A crystal structure of Scapharca dimeric hemoglobin. Cooperativity based on directly communicating hemes at a novel subunit interface.

The crystal structure of the cooperative dimeric hemoglobin from the arcid clam, Scapharca inaequivalvis, has been determined in the carbonmonoxy state. The phase problem was solved for reflections with Bragg spacings greater than 3 A using anomalous scattering from the porphyrin iron atoms measured at a single wavelength in combination with molecular averaging. The model built into this electron density map has been refined at 2.4 A resolution by means of stereochemically restrained least squares minimization to a conventional R-value of 0.156. The root mean square deviation from ideal bond lengths and angles are 0.013 A and 1.7 °, respectively. In addition to the 2336 hemoglobin atoms, 214 water molecules have been incorporated into the model. This structure reveals the details of an assemblage of two identical myoglobin-like subunits that is radically different from vertebrate hemoglobins. The subunit interface is formed by direct apposition of the E and F helices, whereas these surfaces are external in vertebrate hemoglobins. The interface has both hydrophobic and hydrophilic character. Two symmetrically related hydrophobic regions are formed between subunits. Six residues are involved in each of these regions that pack tightly enough to exclude water but have only a few atoms in close van der Waals contact. A number of ordered water molecules line the interface and form bridging hydrogen bonds between subunits. Four intersubunit ionic interactions are formed, two of which involve negatively charged propionate groups of the porphyrin. In contrast to cooperative vertebrate hemoglobins, a hydrogen bond network provides a direct route for communication between the two heme groups

Tunneling Splittings in Mn12-Acetate Single Crystals

A Landau-Zener multi-crossing method has been used to investigate the tunnel splittings in high quality Mn$_{12}$-acetate single crystals in the pure quantum relaxation regime and for fields applied parallel to the magnetic easy axis. With this method several individual tunneling resonances have been studied over a broad range of time scales. The relaxation is found to be non-exponential and a distribution of tunnel splittings is inferred from the data. The distributions suggest that the inhomogeneity in the tunneling rates is due to disorder that produces a non-zero mean value of the average transverse anisotropy, such as in a solvent disorder model. Further, the effect of intermolecular dipolar interaction on the magnetic relaxation has been studied.Comment: Europhysics Letters (in press). 7 pages, including 3 figure

Verification of Identifications of Cyprinid Specimens from the Colorado River Basin, Texas

Numerous published reports indicate that records of occurrence of Sharpnose Shiner, Notropis oxyrhynchus, in the Colorado River basin of Texas are the result of an introduction, though the species is clearly native in the adjacent Brazos River basin. We discovered previously mis-identified specimens of N. oxyrhynchus that extend the record of presence of the species in the Colorado basin much further back in time than previous authors realized, and conclude that the species was almost certainly native there. However, lack of the species in any of the many collections made in the basin over the last half century indicates a low probability that it still persists there.U.S. Fish & Wildlife Service, Arlington, Texas. FWS FBMS Agreement #: F12AP00622; CFDA Number/Title: 15.650; non-Profit, AcademicTexas Natural Science Cente

Using the Fishes of Texas Project Databases and Recent Collections to Detect Range Expansions by Four Fish Species on the Lower Coastal Plain of Texas

The Fishes of Texas project online database is a large, freely available quality controlled fish occurrence database of museum vouchered specimens. We used data from it, the same project’s separate database of occurrences extracted from published literature and our own recent survey data to examine range stability for four fish species inhabiting the Texas Lower Coastal Plain: Fundulus chrysotus, Fundulus jenkinsi, Heterandria formosa and Poecilia formosa. A weakness of our data is that they consist of presences only and species absences can only rarely be inferred. To help adjust for this we used common widespread species as proxies for the four target species by using captures of these proxy species as indicators that the collecting methods used were appropriate to capture the target species, assuming then that large numbers of occurrences of the proxies with contemporaneous absence of the target species in the same samples supports inferences of probable absence of target species. We here report new and previously unpublished occurrences for these species and document westward range expansions for H. formosa and F. chrysotus, an eastward range expansion for P. formosa, and a pattern of possible range contraction and expansion for F. jenkinsi

Preliminary Results of American Eel Sampling Efforts in Gulf of Mexico Drainages of Texas

American Eel Anguilla rostrata has a unique and complex life history that is fairly well-studied on the eastern coast of the United States, but few studies have been done on Gulf of Mexico drainages. To inform conservation and management decisions, efforts to better understand the population structure, seasonal dynamics, and life history of American Eel are underway. The primary objectives of our efforts are to assess the current and historical distribution and abundance, habitat use, movement patterns, parasite occurrence, diet and population structure of American Eel across all life stages in Gulf of Mexico drainages of Texas.Texas State Wildlife Grant Program grants T-173-R-1 and T-172-R-1 in cooperation with the U.S. Fish and Wildlife Service, Wildlife and Sport Fish Restoration ProgramIntegrative Biolog