David A. Neely

Phylogeny, diversity, and species delimitation of the North American Round-Nosed Minnows (Teleostei: Dionda), as inferred from mitochondrial and nuclear DNA sequences

Accurate delimitation of species is a critical first step in protecting biodiversity. Detection of distinct species is especially important for groups of organisms that inhabit sensitive environments subject to recent degradation, such as creeks, springs, and rivers in arid or semi-desert regions. The genus Dionda currently includes six recognized and described species of minnows that live in clear springs and spring-fed creeks of Texas, New Mexico (USA), and northern Mexico, but the boundaries, delimitation, and characterization of species in this genus have not been examined rigorously. The habitats of some of the species in this genus are rapidly deteriorating, and many local populations of Dionda have been extirpated. Considering the increasing concerns over degradation of their habitat, and pending a more detailed morphological revision of the genus, we undertook a molecular survey based on four DNA regions to examine variation over the range of the genus, test species boundaries, and infer phylogenetic relationships within Dionda. Based on analyses of two mitochondrial (cytb and D-loop) and two nuclear (Rag1 and S7) DNA regions from specimens collected throughout the range of Dionda, we identified 12 distinct species in the genus. Formerly synonymized names are available for two of these species, and four other species remain undescribed. We also redefine the known range of six species. The limited distribution of several of the species, coupled with widespread habitat degradation, suggests that many of the species in this genus should be targets for conservation and recovery efforts.

Two new sculpins of the genus cottus (Teleostei: Cottidae) from rivers of eastern north America

Abstract Two new species of freshwater sculpins are herein described from the Gulf Slope of the southeastern United States. The Tallapoosa Sculpin, Cottus tallapoosae, is restricted to the Tallapoosa River drainage, a tributary to the Mobile Basin, above the Fall Line in Alabama and Georgia, while the Chattahoochee Sculpin, Cottus chattahoochee, is restricted to the Chattahoochee River drainage, a tributary to the Apalachicola River, above the Fall Line in Georgia. Both differ from other North American sculpins primarily in having modally eight infraorbital canal pores and five suborbitals (otherwise shared only with Cottus paulus). Cottus tallapoosae and C. chattahoochee differ from each other primarily with the former having an incomplete lateral line and reduced or absent post-pectoral prickling, whereas the latter usually has a complete lateral line and a well-developed postpectoral patch. Cottus tallapoosae is the sixth species of fish endemic to the Tallapoosa River drainage, while Cottus chattahoochee is the eighth species endemic to the Apalachicola River drainage. Both species are widespread above the Fall Line and locally abundant. They typically inhabit rocky shoals and riffles of small upland streams, but are occasionally found in larger rivers.

Status of the Yaqui Catfish (Ictalurus pricei) in the United States and Northwestern Mexico

Abstract To appraise conservation status of the Yaqui catfish Ictalurus pricei, we reviewed literature and unpublished records on a captive stock, examined voucher specimens at museums, re-sampled historical localities in the Yaqui, Mayo, and Fuerte river basins, and we surveyed rivers further south. A total of 72 specimens of native Ictalurus was collected in the Yaqui, Fuerte, Sinaloa, Culiacán, and San Lorenzo river basins. No native Ictalurus was collected in the Mayo Basin. Distribution of the Yaqui catfish appears restricted to the Yaqui, Mayo and Fuerte river basins, all of which now harbor nonnative blue (I. furcatus) and channel (I. punctatus) catfishes. The nonnative black bullhead (Ameiurus melas) is now known from the Yaqui Basin and the flathead catfish (Pylodictis olivaris) has been recorded anecdotally in the Yaqui Basin. Threats to the Yaqui catfish have increased in recent years and hybridization with the channel catfish now appears widespread. We conclude that the Yaqui catfish should be considered endangered throughout its range and that status of native populations of Ictalurus in the United States and Mexico should be reviewed and management intensified.

Summer Stream Temperatures Influence Sculpin Distributions and Spatial Partitioning in the Upper Clark Fork River Basin, Montana

The upper Clark Fork River basin of western Montana supports a poorly understood sculpin (Uranidea spp.) fauna that has perplexed ichthyologists and fish ecologists since the late 1800s. During our study, the basin contained three sculpin taxa whose taxonomy was under revision. All three taxa were formerly referred to the genus Cottus but are now treated as Uranidea. Our goal was to improve understanding of the distribution and ecology of two of the taxa. From 2006 to 2009, we sampled 144 reaches in 31 streams and rivers to determine distributions of each taxa across the study area and within streams. We collected habitat data in 2007 and stream temperature data from 2006–2009 to identify correlates of sculpin distributions. In streams where both taxa occurred, Rocky Mountain Sculpin Uranidea sp. cf. bairdii were downstream and Columbia Slimy Sculpin U. sp. cf. cognata were upstream with a syntopic zone in between. Summer stream temperatures strongly influenced sculpin distributions, with mean August 2007 water temperatures increasing in order of reaches characterized as: Columbia Slimy Sculpin-dominated, syntopic, Rocky Mountain Sculpin-dominated, and no sculpin. Columbia Slimy Sculpin occurred in cold tributaries of the Blackfoot, Clark Fork, and Bitterroot rivers and in two coldwater refugia in the mainstem Bitterroot River. In contrast, Rocky Mountain Sculpin occupied warmer downstream segments of many Blackfoot and Clark Fork river tributaries as well as some mainstem reaches of both rivers but were absent from the Bitterroot River drainage. Persistence of the taxa will likely depend, both directly and indirectly, on future water temperatures, and thus, sculpins are appropriate targets for researching and monitoring biological changes resulting from climate change.

First Records of Rhinogobius lindbergi (Teleostei: Gobiidae) and Abbottina rivularis (Teleostei: Cyprinidae) in the Lake Buyr Drainage, Mongolia

ABSTRACT We report the first records of Amur goby, Rhinogobius lindbergi and the Chinese false gudgeon, Abbottina rivularis from the Lake Buyr drainage of eastern Mongolia. Both species were previously known only from much farther downstream in the Amur River basin. Because of their abundance at three sites separated by 11 km in Lake Buyr and a tribuary stream, and presence of multiple size classes, we strongly suspect that these species are established. Both species have been widely dispersed outside of the Amur River basin as contaminants in cultured, large-bodied cyprinids (Ctenopharyngodon, Hypophthalmichthys, Parabramis), and we suggest that this is the most likely means of their introduction into Lake Buyr. The long-term impacts of these species on the native ichthyofauna are unknown, but unlikely to be positive. We suggest that immediate measures be taken to monitor their dispersal, and to prevent similar introductions in the future.

Table 3 Adams_et_al_2015

Table 3. Minimum, average, and maximum daily water temperature values for each reach during summer 2007. Stream names and reach codes are as in Tables 1 and 2. Sites are organized by sculpin group: no sculpin (none); Rocky Mountain sculpin (RMS) or Columbia slimy sculpin (CSS) only; or both species (syntopic). Daily summary statistics (mean, sample size [N], SD, and SE) by group are given for each temperature metric. Numbers in blue were estimated based on linear regressions (see text).