Catostomid Fishes Research Articles

Avoiding paralogy: diploid loci for allotetraploid blue sucker fish (Cycleptus elongatus, Catostomidae)

The blue sucker (Cycleptus elongatus) is a widespread North American catostomid fish that appears to be declining throughout much of its range. Here, we describe the isolation and characterization of eleven microsatellite loci developed for population genetic studies in the genus. We show that an additional step of cloning and sequencing can be useful in isolating paralogous loci that often co-amplify in polyploid organisms. Finally, we present results of cross-species amplifications tests in nine other taxa, including four catostomids.

THE MYXOZOAN FAUNA OF SPOTTAIL SHINER IN THE GREAT LAKES BASIN: MEMBERSHIP, RICHNESS, AND GEOGRAPHICAL DISTRIBUTION

Spottail shiner (Notropis hudsonius) from localities in each of the Great Lakes plus some nearby waterbodies, i.e., the St. Lawrence River, and the Chester River, Maryland, were examined for myxozoan parasites. A total of 10 species was found, including 7 histozoic (Myxobolus sp.; M. algonquinensis Xiao and Desser, 1997; M. bartai Salim and Desser, 2000; M. xiaoi Salim and Desser, 2000; M. fanthami Landsberg and Lom, 1991; M. hendricksoni Mitchell, Seymour, and Gamble, 1985; Thelohanellus notatus Mavor, 1916) and 3 coelozoic (Chloromyxum sp., Zschokkella sp., Sphaerospora sp.) representatives. Infracommunity richness varied from 0 to 5 species per fish; mean infracommunity richness varied from 0 to 2.5 species. Component community richness varied from 0 to 7. Significant positive correlations were observed between mean and maximum infracommunity richness and component community richness. Similarly, maximum prevalence of each species at any 1 site was positively correlated with geographic range as measured by number of localities where a parasite species was encountered. Individual species occurred independently of each other. Representative histozoic and coelozoic species displayed similarly widespread distributions from Wisconsin to Maryland, but overall, histozoic species were dominant members within component communities. The study concludes that, under the present taxonomic paradigm, species parasitizing spottail shiner appear to be part of a larger network that cycles, in varying degrees, through certain other cyprinid and catostomid fish. The challenge of future research is to determine whether each parasite species constitutes single or multiple genetically isolated populations.

Differences in Species Composition and Feeding Ecology of Catostomid Fishes in Two Distinct Segments of the Missouri River, North Dakota, U.S.A.

In 1997 and 1998, we sampled the Missouri River, North Dakota to determine if anthropogenic disturbances had influenced catostomid species composition and feeding ecology. We compared two distinct river segments, the Missouri River between the mouth of the Yellowstone River and Lake Sakakawea (the Yellowstone–Sakakawea segment (YSS)), a moderately altered segment and the Missouri River between Garrison Dam and Lake Oahe (the Garrison–Oahe segment (GOS)), a highly altered segment. The segments exhibited greatly different sucker communities. Bigmouth buffalo, Ictiobus cyprinellus, smallmouth buffalo, Ictiobus bubalus, and river carpsucker, Carpiodes carpio, represented 94% of the sucker catch in the YSS, whereas in the GOS, white sucker, Catostomus commersoni, and longnose sucker, Catostomus catostomus, constituted 98% of the sucker catch. In the YSS, high zooplankton densities led to greater sucker zooplanktivory and food niche overlap than in the GOS. Intense anthropogenic disturbances to the GOS are associated with the differences in sucker species composition, prey density and composition, and sucker feeding ecology between the two segments.

Is chemical contamination responsible for the decline of the copper redhorse ( Moxostoma hubbsi), an endangered fish species, in Canada?

The copper redhorse (Catostomidae: Moxostoma hubbsi) is an endangered fish species whose worldwide distribution is limited to the St. Lawrence River and three of its tributaries, in Canada. Severe reproductive impairment and lack of successful recruitment reported in this species have been hypothetically associated with water pollution. In order to obtain an initial description of contamination levels in copper redhorse, seven accidentally-killed specimens from the Richelieu River were analyzed for trace metals, organochlorine pesticides, chlorobenzenes, PAHs, PCBs, dioxins and furans. Fish varied between 9 and 33 years of age, which corresponds to mature individuals. The levels of contaminants analyzed in different body tissues were close to and often lower than levels reported in other catostomid fish species from nearby locations within the St. Lawrence River basin. Concentrations of total mercury, cadmium and co-planar PCBs increased with fish age. The types and concentrations of contaminants found suggested that the Richelieu River spawning population of copper redhorse would migrate and spend time in the St. Lawrence River. Concentrations of many contaminants were often highest in gonadal tissues, but levels were much lower than reported in the literature as causing reproductive impairment or egg and fry mortality in fish. Further research is needed to assess the potential link between contaminants and reproductive failure in this endangered fish species.

Phylogenetic Relationships of Major Clades of Catostomidae (Teleostei: Cypriniformes) as Inferred from Mitochondrial SSU and LSU rDNA Sequences

Suckers (Family Catostomidae) are holarctic in distribution and include 76 recent species in 14 genera, with 13 genera and 75 species occurring in North and Central America and Siberia. Although this group constitutes a significant component of many aquatic ecosystems, most historic systematic effort has been either alpha- or limited beta-level studies focusing on the two largest tribes within the family, the Catostomini and the Moxostomatini. A recent phylogenetic study based on morphological, biochemical, and early life history characters has advanced current understanding of relationships among catostomid fishes. To further examine phylogenetic relationships among basal lineages of catostomids, we sequenced the entire mitochondrial (mt) SSU and LSU rRNA genes from genera representing all subfamilies and tribes within Catostomidae. Phylogenetic analysis of gene sequences yielded monophyletic Catostomidae, Ictiobinae, and Catostominae and para- or polyphyletic Cycleptinae, with Myxocyprinus as the basal-most taxon and Cycleptus as either the next most-basal taxon or the taxon basal to the Catostominae. Relationships within the Catostominae were generally consistent with those proposed in the above-noted recent phylogenetic study although Thoburnia and Hypentelium were either a clade sister to or a grade group relative to Moxostoma and Scartomyzon. In all trees, Scartomyzon was paraphyletic and embedded within Moxostoma. Phylogenetic affinities of Erimyzon and Minytrema varied depending on data set and character weighting scheme employed. To better reflect phylogenetic relationships resolved in this extensive analysis, we propose the following changes to the classification of catostomids: formation of the new subfamily Myxocyprininae, containing Myxocyprinus from China; restriction of the Cycleptinae to the two species of Cycleptus from North America; restriction of the tribe Moxostomatini to Moxostoma and Scartomyzon; Erimyzon and Minytrema are incertae sedis within Catostominae; and resurrection of the tribe Thoburniini, containing Thoburnia and expanded to include Hypentelium.

A review of the comparative morphology and systematics of Utah Lake suckers (Catostomidae)

AbstractUtah Lake, Utah, U.S.A. harbours an endemic catostomid fish, the June sucker Chasmistes liorus, that is recognized as being endangered. Since 1981, post‐1935 representatives of the June sucker have generally been considered to be examples of a self‐propagating hybrid. Utah Lake has contained another endemic catostomid, the webug sucker Chasmistes fecundus that was regarded as a true species until 1981 when it was judged to be an extirpated sterile hybrid. Since then, fisheries biologists have not attempted to identify it. This review makes a comparative examination of the published descriptions of the internal and external anatomy of these two species, plus the third catostomid of Utah Lake, the Utah sucker Catostomus ardens. The Utah sucker purportedly crossed with a form of the June sucker that has supposedly since been expunged, to produce hybrids. On the basis of comparative morphology and the consideration of temporal changes in the habitat and piscifauna of Utah Lake, the authenticity of supposed hybridism in the webug sucker, and in the contemporary June sucker, is analysed. The conclusion is reached that there is insufficient evidence to deem these taxa hybrids, or the webug sucker, extinct.

Microstratigraphic study of meristic variation in an Eocene fish from a 10 000-year varved interval at Horsefly, British Columbia

Varved, lacustrine rocks of the Middle Eocene Horsefly deposits in British Columbia are ideal for microstratigraphic studies. Temporal resolution in such varved deposits can theoretically be as small as a year. In the Horsefly beds, specimens can be assigned precisely to their position in the stratigraphic section by comparing the laminations enclosing the fossils with those of a reference section. Each fossil can thus be assigned to a relative year of death. Some 700 specimens of the catostomid fish Amyzon aggregatum from the 10 000-year "H3" varved interval are examined for meristic variation. Very few of the meristic variables are significantly correlated with each other. Meristic series that are the last to develop ontogenetically are also the most phenotypically variable. In the studied interval, meristic variation has a strong temporal component, particularly in the case of fin rays and in the ratio between precaudal and caudal vertebral counts. Much, but not all, of this temporal variation occurs in conjunction with environmental changes in the lake as estimated by taphonomy and is consistent with some combination of ecophenotypic and (or) evolutionary responses of the fish population to the environmental change.

Sequence analysis and tissue expression of a non-Bohr beta-globin cDNA from Atlantic salmon

The presence of a haemoglobin protein which does not exhibit a Bohr effect has been found only in fish living in fast flowing waters. We report the cloning of the first non-Bohr effect beta-globin cDNA from an adult Atlantic salmon kidney bank. Nucleotide sequence analysis of this cDNA shows that the predicted beta-globin peptide comprises 147 amino acids with a calculated molecular mass of 15 975 Da and an overall amino acid homology of 40 to 50% to higher vertebrates and 60–90% to fish sequences. This sequence confirms the important amino acid residues which are changed thus causing loss of the Bohr effect [Powers, D.A. and Edmunson, A.B. (1972) Multiple hemoglobins of catostomid fish. J. Biol. Chem. 247, 6686–6693; Brunori, M. (1975) Molecular adaptation to physiological requirements: the hemoglobin system of trout. Curr. Topics Cell. Regul. 9, 1–39]. This loss allows the haemoglobin protein to have a higher oxygen affinity, as it does not release oxygen when the pH of the surrounding environment decreases, which is an important ability for the fish in times of stress.

Mitochondrial DNA Diversity within and among Populations of Razorback Sucker (Xyrauchen texanus) as Determined by Restriction Endonuclease Analysis

Genetic variation within and among populations of razorback sucker (Xyrauchen texanus) an endangered catostomid fish endemic to the Colorado River basin of western North America, was examined by restriction endonuclease analysis of mtDNA. MtDNA from 143 specimens was cleaved with eight 4and 6-basepair-recognizing restriction endonucleases, delineating 38 haplotypes. Withinpopulation heterogeneity varied clinally. Diversity and number of haplotypes declined progressively downto upstream. Most variation was within instead of between populations, and phylogenetic and phenetic approaches identified no geographic structure of haplotype networks. Thus, samples were from remnants of a single population that formerly occupied the entire basin. Clinal variation of within-population heterogeneity likely reflects either nonequilibrium conditions due to Holocene expansion northward from a southern refugium or climate-associated variation in population sizes. Because historical gene exchange seemed sufficient to preclude population divergence, conservation strategies treating the imperiled species as a single population are appropriate.

Mitochondrial DNA Variability in the Endangered Razorback Sucker (Xyrauchen texanus): Analysis of Hatchery Stocks and Implications for Captive Propagation

The razorback sucker (Xyrauchen texanus) is a large, long‐lived catostomid fish endemic to the Colorado River drainage of western North America, endangered because of recruitment failure. Efforts to preserve the species have emphasized artificial propagation and reintroduction. Given the importance of maintaining genetic diversity in such a program, we examined mitochondrial DNA diversity in a source population (Lake Mohave, Arizona‐Nevada) and three hatchery‐produced year classes (1987, 1989, 1990). The source contained considerable variation, indicated by high haplotype diversity (ĥ = 0.97) and a large number of unique haplotypes (17 in 25 individuals). Diversity also was high in the 1987 (ĥ = 0.89, 6 haplotypes in 10 individuals) and 1989 hatchery‐produced year classes (ĥ = 0.91, 7 in 11), but significantly lower in the 1990 year class (ĥ = 0.71, 4 in 10). Low diversity in the last class was likely because of differences among females in fecundity, viability of progeny, or both. Because natural populations have collapsed throughout the species’ range, we must identify methods that preserve the most diversity. We examined three potential alternatives: standard hatchery propagation, natural spawning in predator‐free environments, and protective custody of larvae collected from the lake with reintroduction after growth to a size likely to survive. The last is the preferred alternative and should be pursued as the most cost‐effective option for preserving genetic diversity in the razorback sucker.

Tests of the annual hypothesis and temporal calibration of a 6375‐varve fish‐bearing interval, Eocene horsefly beds, British Columbia, Canada

Eocene lake sediments from Horsefly, British Columbia are rich in fossils of the catostomid fish Amyzon aggregatum. Previous studies of this fish in a 700‐year sequence of varves have demonstrated their potential use in studies of fine‐scale temporal variation in taphonomy and morphology. Tests of the annual (varve) hypothesis for the layers, together with reliable temporal calibration, are necessary prerequisites to any such application. In the present study, a longer continuous sequence from this deposit is subjected to additional tests of the annual hypothesis and is temporally calibrated. Tests include spectral analysis of varve thicknesses, scanning electron microscopy and elemental analysis of dark and light laminae, and analysis of within‐couplet distribution of seasonal fossils. Results support the hypothesis that the couplets are true varves. Some 6375 varves occur in the studied interval. Each varve is composed of a diatom‐dominated summer lamina and a winter lamina richer in clays, pyrite, and gypsum. Occasional turbidites and thin layers of volcanic ash allow counting and identification of individual varves under low‐power magnification. Fish are rare in the upper 2000 varves but abundant and extensively distributed in the lower 4000 varves of the sequence, making these a potentially valuable interval for studies of microstratigraphic variation in morphology and taphonomy.

Duplicate Gene Expression and Allozyme Divergence Diagnostic for Catostomus tahoensis and the Endangered Chasmistes cujus in Pyramid Lake, Nevada

The allotetraploid catostomid fish, Catostomus tahoensis and the endangered Chasmistes cujus, from Pyramid Lake, Nevada, were examined electrophoretically for duplicate gene expression and allozyme variation. Both species resemble other advanced catostomids in the retention of relatively few ancestrally duplicated genes: 34% and 36%, respectively. The two species were diagnostically different for 20 genetic characters: number of genes for fructose-bisphosphate aldolase (Fba-A'), tissue expression of an NADP-dependent malate dehydrogenase, and allelic composition at 18 loci. No genetic evidence of hybridization was detected in a sample of 28 C. cujus suspected, on the basis of morphology, to be of hybrid origin.

Pellucidhaptor eriensis n.sp. and Pellucidhaptor thelostea n.sp. (Monogenea: Dactylogyridae) from catostomids (Cypriniformes) found in Lake Erie, Ontario, Canada

A collection of dactylogyrid Monogenea from catostomid fishes taken in Lake Erie, Ontario, Canada, included Pellucidhaptor eriensis n. sp. from Carpiodes cyprinus and Moxostoma macrolepidotum; P. thelostea n.sp. from Moxostoma macrolepidotum and M. anisurum; P. angularis Kritsky and Hathaway, 1969 from Carpiodes cyprinus; P. micracanthus Kritsky, Leiby, and Shelton, 1972 from Carpiodes cyprinus; P. moxostomi Mergo and White, 1982 from Moxostoma anisurum (new Canadian record) and P. nasalis Dechtiar, 1969 from Catostomus commersoni. Pellucidhaptor eriensis is differentiated from other Pellucidhaptor species by the shape of the superficial root of the dorsal hamuli, the shape of the dorsal bar, and the configuration of the male copulatory apparatus. Pellucidhaptor thelostea is readily distinguished from other members of the genus by the sclerotized "wishbone"-shaped support of the male copulatory organ. Supplementary data are provided for the previously described species and an updated list of parasite–host records is included.

Do brook charr (Salvelinus fontinalis) from insular Newfoundland have different parasites than their mainland counterparts?

Based on the published literature, comparison of the metazoan parasite faunas of brook char (Salvelinus fontinalis) from freshwater localities in northeastern North America reveals that hosts in insular Newfoundland have fewer parasite species recorded from them. Of 45 parasite species or taxa, only 20 are common to the island and the mainland. Twenty-three parasite species have been reported from the mainland but not from the island, with most of the taxa being types common to non-salmonid fishes. Two species, the copepod Ergasilus luciopercarum and the digenean Tetracotyle, have been reported from charr on the island but not from the northeastern mainland. It is suggested that the primary reason for the difference in the structure of the assemblages is the lack of contact brook charr in Newfoundland have with percid, cyprinid, centrarchid, esocid, and catostomid fishes and their parasites.

A review of species of Myxobolus (Myxosporea) parasitizing catostomid fishes, with a redescription of Myxobolus bibullatus (Kudo, 1934) n.comb. and description of Myxobolus lamellus n.sp. from Catostomus commersoni in Nova Scotia

Known species of Myxobolus from catostomid fishes are reviewed and Myxobolus bibullatus (Kudo, 1934) n.comb. and Myxobolus lamellus n.sp. (Myxosporea) are described from common sucker (Catostomus commersoni) in Sawler Lake, Lunenburg County, Nova Scotia. Trophozoites of M. bibullatus form saclike interlamellar cysts at the base of gill filaments. Myxobolus lamellus n.sp. forms interstitial trophozoites in secondary lamellae that envelop the capillary bed. Spores form through the cyst's vacuolated matrix, and are round with large polar capsules relative to spore length. Ten species of Myxosoma from catostomids are transferred to Myxobolus and the following revisions made: Myxobolus bibullatus (Kudo, 1934) n.comb. (syn. Myxosoma bibullatum Kudo, 1934); Myxobolus commersonii (Fantham, Porter, and Richardson, 1939) n.comb. (syn. Myxosoma commersonii Fantham, Porter, and Richardson 1939); Myxobolus ellipticoides (Fantham, Porter and Richardson, 1939) n.comb. (syn. Myxosoma ellipticoides Fantham, Porter, and Richardson 1939); Myxobolus endovasus (Davis, 1947) n.comb. (syn. Myxosoma endovasa Davis, 1947); Myxobolus microthecus (Meglitsch, 1942) n.comb. (syn. Myxosoma microthecum Meglitsch, 1942); Myxobolus multiplicatus (Reuss, 1906) n.comb. (syn. Myxosoma multiplicatum (Reuss, 1906); and Myxobolus ovalis (Davis, 1923) n.comb. (syn. Myxosoma ovalis Davis, 1923). Myxobolus meglitschi (Meglitsch, 1937) nom.nov (syn. Myxosoma rotundum Meglitsch, 1937), Myxobolus musculosus (Kudo, 1923) nom.nov. (syn. Myxosoma catostomi Kudo, 1923), and Myxobolus filamentus (Rice and Jahn, 1943) nom.nov. (syn. Myxosoma okobojiensis Rice and Jahn, 1943) are established because of specific preoccupations. Known information on myxobolids from catostomid fishes is summarized.

Morphology and Foods of Arizona Catostomid Fishes: Catostomus insignis, Pantosteus clarki, and Their Putative Hybrids

Morphology and food habits of putative hybrids between two widespread western American catostomid fishes, Catostomus insignis (Sonora sucker) and Pantosteus clarki (desert sucker), were compared with their parental forms. Hybrid intermediacy was demonstrable in morphological characters that differed between parental fishes, although tendencies were toward C. insignis. Coefficients of variation were similar in hybrid and parental samples, which, along with relatively low variation in canonical variables of discriminant function analysis, implied a lack of backcrossing. Foods of hybrids averaged intermediate to parental forms, but variation was high. Hybrids utilized a broad food base, with feeding habits that collectively spanned those of each parent. Additive inheritance of morphological and behavioral traits seems influenced by dominance and/or interallelic suppression that tend to produce deviations from often-assumed intermediacy in hybrid fishes.

Contributions of Developmental Characters to a Phylogeny of Catostomid Fishes, with Comments on Heterochrony

Characteristics of larval stages were examined to develop a hypothesis of evolutionary relationships among living catostomid fishes for comparison with adult-based hypotheses. The final set of 30 characters included morphometric measures, myomere counts, relative timing of developmental events and presence of distinctive pigmentation. In all, 17 species representing all but 2 of 11 extant genera were included. Hypotheses were constructed using cladistic principles with character polarity established by cyprinid outgroup comparison. The best estimate of phylogeny based on the observed character states was similar to adult-based concepts of relationships. Subfamilies and tribes sorted well, but developmental characters did not demonstrate monophyly of these taxa. Ictiobines were most primitive. The catostomine tribe Erimyzontini was not recognized; Erimyzon was allied with the ictiobines and Minytrema with Moxostoma.

Gyrodactylus fryi n. sp. (Monogenea) from Esox masquinongy Mitchill in Ontario

Gyrodactylus fryi n. sp. (Monogenea) is described from the body surface of Esox masquinongy Mitchill in Ontario. Gyrodactxlus fryi resembles most closely G. lingulatus Rogers, 1968 from the cyprinid Hypentelium etowanum (Jordan) in Alabama in having well-developed hamuli, a compact ventral bar with no anterolateral processes, a tongue-shaped ventral bar membrane, and a penis with small spines in two arched rows. Gyrodactylus fryi is easily distinguished from G. lingulatus by marginal hook size (11 to 14 μm long. 7 to 8 μm wide proximally, 14 to 16 μm wide distally) and shape (relatively small base with a long thin blade). Gyrodactylus fryi resembles at least nine other Gyrodactylus species known from cyprinid and catostomid fishes. The study concludes that a close ecological association between a piscivorous ancestral E. masquinongy and cyprinid and (or) catostomid fishes led eventually to evolutionary radiation of a gyrodactylid lineage from prey to predator.

Archinephric duct lesions caused by Phyllodistomum superbum and P. lysteri (Digenea: Gorgoderidae) in catostomid fishes.

Archinephric duct lesions caused by Phyllodistomum superbum and P. lysteri (Digenea: Gorgoderidae) in catostomid fishes.

Amyzon gosiutensis, a New Catostomid Fish from the Green River Formation

cene deposits is osteologically indistinguishable from living species (Miller, 1965). Plio-pleistocene catostomids (represented mostly by disarticulated incomplete skeletons) have been studied in detail by Smith (1975), Miller and Smith (1981) and others. Little is known, however, about the structure and relationships of Early Coenozoic catostomids. The Eocene-Oligocene catostomid genus Amyzon was first described by Cope (1872) from Oligocene specimens collected in Nevada. Three additional Oligocene Amyzon species have been described from Colorado (Cope, 1884) and two Middle Eocene species from British Columbia (Cope, 1893; Wilson, 1977). A Late Eocene or Early Oligocene Amyzon is known from Oregon (Cavender, 1968). Cavender (1973, at 53rd annual ASIH meeting) first reported the occurrence of a catostomid in the Green River Formation, based on a poorly preserved partial specimen in the United States National Museum (USNM 175357). In this paper we describe Amyzon gosiutensis, n. sp., from the Laney Shale Member of the early Middle Eocene (Bridgerian) Green River Formation of Wyoming. This is the first catostomid described from the Green River For-