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Mark V. H. Wilson - One of the best experts on this subject based on the ideXlab platform.
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Centrum growth patterns provide evidence for two small taxa of Hiodontidae in the Cretaceous Dinosaur Park Formation
Canadian Journal of Earth Sciences, 2007Co-Authors: Michael G. Newbrey, Mark V. H. Wilson, Allan C. AshworthAbstract:Disarticulated centra recovered from the Campanian Dinosaur Park Formation (Cretaceous) are used to de- scribe hiodontid age, growth, and longevity. Previous studies of Cretaceous centrum morphology have shown only one morphotype. However, growth characteristics can be used to test the one-taxon hypothesis. Age and growth characteris- tics indicate that Cretaceous hiodontids were shorter-lived (i.e., 7 years) and significantly smaller than extant Hiodon. The fossil centra also exhibit two significantly different growth patterns. Initially it was predicted that two factors could explain the presence of the two growth patterns: (1) sexual size dimorphism, and (2) variation in centrum size from multiple species. Sexual size dimorphism did not produce the two growth patterns because (1) H. alosoides maximum total length is significantly correlated with temperature, and (2) the paleotemperature in the depositional environment fluctuated approximately 6 °C mean annual temperature resulting in continuous growth variation. Concerning the sec- ond factor, the coefficient of variation (CV) observed in the Cretaceous centrum size data (0.23 CV) is 22% greater than that of the two extant species of Hiodon combined (0.18 CV) suggesting that at least two species of hiodontids were present in the Dinosaur Park Formation. The distribution of sizes of the smaller Cretaceous centra is not different from one extant species but is significantly different from two species suggesting that three taxa were not present.
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Review of Eohiodon (Teleostei: Osteoglossomorpha) from western North America, with a phylogenetic reassessment of Hiodontidae
Journal of Paleontology, 1997Co-Authors: Mark V. H. Wilson, Lance GrandeAbstract:Review of recently collected material of Eohiodon from North America suggests that there are two valid species, E. rosei (Hussakof) and E. woodroffi Wilson. Eohiodon falcatus Grande is identical to E. woodruffi in known skeletal features and nearly all meristic features and is treated as a junior synonym of the latter. The fossil genus Eohiodon Cavender differs from Hiodon Lesueur, which is known from both fossil and extant species, in numerous meristic and osteological features. The caudal skeleton in Eohiodon is nearly identical to that in Hiodon. The traditionally accepted Notopteroidei, containing Lycopteridae, Hiodontidae, and Notopteridae, is a polypheletic group. The Asian fossil family Lycopteridae is not more closely related to Hiodontidae than it is to other taxa in the Osteoglossomorpha, but is sister to all other Osteoglossomorpha. The Hiodontiformes sensu stricto, including only the family Hiodontidae, is the sister-group of the Osteoglossiformes. This family is not more closely related to notopterids than to other taxa in Osteoglossiformes. The Notopteridae are most closely related to the Mormyroidea; together they and the fossil family Ostariostomidae constitute the sister-group of the Osteoglossoidei. Fossil records of Hiodontiformes sensu stricto and Notopteroidei indicate a widespread pre-Neogene biogeographic range of these freshwater teleosts, suggesting that extinction must have beer, involved in the Cenozoic evolution of these two osteoglossomorph sublineages.
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An Eocene species of Hiodon from Montana, its phylogenetic relationships, and the evolution of the postcranial skeleton in the Hiodontidae (Teleostei)
Journal of Vertebrate Paleontology, 1994Co-Authors: Li Guo-qing, Mark V. H. WilsonAbstract:ABSTRACT Hiodon is a Recent genus of fishes endemic to the fresh waters of North America; it is represented by two species: Hiodon tergisus Lesueur and H. alosoides (Rafinesque). Two specimens of osteoglossomorph collected from the Eocene-Oligocene Kishenehn Formation of northwestern Montana represent a new fossil species that is more closely related to the Recent Hiodon than it is to the Eocene †Eohiodon. The close relationship of this new species to Hiodon is supported by derived characters of the nasal, the opercular series, the jaws, the basihyal tooth plate, the infraorbitals, and the caudal skeleton. Comparative study of the postcranial skeleton of Recent and fossil hiodontids illustrates several stages in the evolution of the Hiodontidae: 1) origin of seven-rayed pelvic fins by the late Early Cretaceous (evidenced by †Yanbiania); 2) development of an anal fin larger than the dorsal fin and supported by 16 or more anal pterygiophores at least as early as the early Late Cretaceous (evidenced by †Ples...
Anindo Choudhury - One of the best experts on this subject based on the ideXlab platform.
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Ex Uno Plures? Morphotype and Lineage Diversity of Bothriocephalus (Cestoda: Bothriocephalidea) in North American Freshwater Fishes.
The Journal of parasitology, 2020Co-Authors: Anindo Choudhury, Tomáš ScholzAbstract:Morphological and molecular evaluation of tapeworms of the genus Bothriocephalus Rudolphi, 1808 (Cestoda: Bothriocephalidea), based on newly collected and uniformly fixed worms from freshwater fishes in Canada and the United States has revealed unexpected diversity. With a combination of selected morphological features and 4 molecular markers (18S rDNA V8 region, ITS1, ITS2, and COI gene sequences), the following morphotypes and lineages of the Bothriocephalus cuspidatus Cooper, 1917 complex were identified, several of which are specific to their respective fish definitive hosts and may represent separate species: B. cuspidatus sensu stricto from walleye, Sander vitreus (type host), which likely includes a miniature morphotype from Johnny darter, Etheostoma nigrum (both Percidae); Bothriocephalus morphotype from pumpkinseed, Lepomis gibbosus (Centrarchidae); and Bothriocephalus morphotype from rock bass, Ambloplites rupestris (Centrarchidae). The Bothriocephalus morphotype from goldeye, Hiodon alosoides (Hiodontidae), may also represent a separate lineage (possibly Bothriocephalus texomensisSelf, 1954) but requires additional studies. A morphotype from smallmouth bass, Micropterus dolomieu, based on a single specimen, is morphologically and genetically very similar to the morphotype from rock bass. Morphological study of the scolex and strobila of heat-killed and fixed specimens has revealed consistent differences, often subtle, that allowed us to differentiate between these morphotypes.
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parasites cnidaria trematoda cestoda nematoda crustacea of select fishes lepisosteidae catostomidae Hiodontidae cyprinidae ictaluridae of lake texoma oklahoma
Proceedings of the Oklahoma Academy of Science, 2019Co-Authors: Chris T Mcallister, Anindo Choudhury, Donald G Cloutman, Stanley E Trauth, Henry W RobisonAbstract:Twenty-seven fishes, including a Longnose Gar (Lepisosteus osseus), a Shortnose Gar (L. platostomus), three Goldeye (Hiodon alosoides), eight Highfin Carpsucker (Carpiodes velifer), a Bigmouth Buffalo (Ictiobus cyprinellus), four Smallmouth Buffalo (I. bubalus), a Common Carp (Cyprinus carpio), five Blue Catfish (Ictalurus furcatus), two Channel Catfish (Ictalurus punctatus), and a Flathead Catfish (Pylodictus olivaris) were collected in February 2017 and February 2018 from several sites on Lake Texoma, Oklahoma, and examined for parasites. Thirteen taxa of parasites were found, including two myxozoans (Henneguya spp.), seven cestodes (Proteocephalus ambloplitis, Essexiella fimbratum, Megathylacoides sp., Pseudoglaridacris confusa, Promonobothrium currani, Khawia sp., and Bothriocephalus sp.), two digeneans (Crepidostomum illinoiense and Macroderoides sp.), a larval nematode (Contracaecum sp.), and a copepod (Ergasilus cerastes) were harbored by these hosts. We document several new host and distributional records for these parasites, including new state records for Oklahoma.
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Phylogenetic Relationships of Spiruromorph Nematodes (Spirurina: Spiruromorpha) In North American Freshwater Fishes
The Journal of parasitology, 2018Co-Authors: Anindo Choudhury, Steven A. NadlerAbstract:Abstract Nematodes are common in the parasite communities of North American freshwater fishes, and the majority of them belong to 1 conventional order, Spirurida Chitwood, 1933. Within the Spirurida, the superfamilies Habronematoidea Chitwood and Wehr, 1932 and Thelazioidea Sobolev, 1949 have undergone considerable diversification. The dominant families of these 2 superfamilies, Cystidicolidae Skrjabin 1946 and Rhabdochonidae Railliet, 1916, respectively, are particularly common, widely distributed, and diverse, especially in North America, yet their phylogenetic relationships remain largely unexplored. In this study, we use near complete sequences of the 18S rRNA genes (SSU rDNA) from species in 6 genera (Capillospirura Skrjabin, 1924, Cystidicola Fischer, 1798, Salmonema Moravec, Santos and Brasil-Sato, 2008, Rhabdochona Railliet, 1916, Spinitectus Fourment, 1883, and a putative new cystidicolid in mooneyes, Hiodontidae), along with a species of Hedruris Nitzsch, 1812 from newts as a surrogate for the f...
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Redescription of Crepidostomum opeongoensis Caira, 1985 (Trematoda: Allocreadiidae) from fish hosts Hiodon alosoides and Hiodon tergisus (Osteichthyes: Hiodontidae).
The Journal of parasitology, 2000Co-Authors: Anindo Choudhury, Patrick A. NelsonAbstract:Crepidostomum opeongoensis Caira, 1985 (Trematoda: Allocreadiidae) is redescribed from fish hosts Hiodon alosoides and Hiodon tergisus in southern Manitoba. The redescription adds details regarding the surface morphology and reproductive structures of the parasite not described previously. These include the characteristic tegumental papillae around the oral opening, paired papillae on the ventral and dorsal surfaces of the body, and tegumental bosses on the dorsal surface of the fore-body. Crepidostomum opeongoensis co-occurred with its hypothesized sister species, Crepidostomum illinoiense, in all host individuals harboring the former, and both species are characteristic of hiodontids. The association of C. opeongoensis with hiodontids and the absence of hiodontids in Lake Opeongo where C. opeongoensis was originally reported indicate that the Algonquin Park region may have had hiodontids in the past and that the life cycle may be completed at present without the original fish host.
J. A. C. Nicol - One of the best experts on this subject based on the ideXlab platform.
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On the eye of the Goldeye Hiodon alosoides (Teleostei: Hiodontidae)
Journal of Zoology, 2009Co-Authors: A. C. G. Best, J. A. C. NicolAbstract:In the eye of the Goldeye the photoreceptors are arranged in bundles and the pigment epithelium contains a massive reflector or tapetum lucidum. Photoreceptor bundles are arranged in parallel rows, the bundles alternating in position from row to row. Each bundle contains about 60 photoreceptors, of which 30 or so are cones. Rod outer segments lie in the scleral half of the outer retinal region of the light-adapted eye. Processes of the pigment epithelium cells extend vitread almost to the external limiting membrane; they envelop the bundles of rods and cones, and a ring of four processes surrounds each bundle. A process contains two kinds of reflecting crystals (composed of uric acid). A large part of the epithelium cell is packed with small disc-shaped crystals (crystallites) enclosed in thin membranes; the tip of the process, in the region of the photoreceptor bundle, contains orderly arrays of small rod-shaped crystals (rodlets). It is suggested that the crystallites form a diffuse reflector backscattering light into the rods; and that the rodlets reflect light regularly from their surfaces into the photoreceptor bundles. In the light-adapted state, rods are enveloped by pigment and crystallites. The organization is compared with that of other fishes that have photoreceptors in bundles (grouped retinae) and tapeta lucida.
Li Guo-qing - One of the best experts on this subject based on the ideXlab platform.
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An Eocene species of Hiodon from Montana, its phylogenetic relationships, and the evolution of the postcranial skeleton in the Hiodontidae (Teleostei)
Journal of Vertebrate Paleontology, 1994Co-Authors: Li Guo-qing, Mark V. H. WilsonAbstract:ABSTRACT Hiodon is a Recent genus of fishes endemic to the fresh waters of North America; it is represented by two species: Hiodon tergisus Lesueur and H. alosoides (Rafinesque). Two specimens of osteoglossomorph collected from the Eocene-Oligocene Kishenehn Formation of northwestern Montana represent a new fossil species that is more closely related to the Recent Hiodon than it is to the Eocene †Eohiodon. The close relationship of this new species to Hiodon is supported by derived characters of the nasal, the opercular series, the jaws, the basihyal tooth plate, the infraorbitals, and the caudal skeleton. Comparative study of the postcranial skeleton of Recent and fossil hiodontids illustrates several stages in the evolution of the Hiodontidae: 1) origin of seven-rayed pelvic fins by the late Early Cretaceous (evidenced by †Yanbiania); 2) development of an anal fin larger than the dorsal fin and supported by 16 or more anal pterygiophores at least as early as the early Late Cretaceous (evidenced by †Ples...
A. C. G. Best - One of the best experts on this subject based on the ideXlab platform.
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On the eye of the Goldeye Hiodon alosoides (Teleostei: Hiodontidae)
Journal of Zoology, 2009Co-Authors: A. C. G. Best, J. A. C. NicolAbstract:In the eye of the Goldeye the photoreceptors are arranged in bundles and the pigment epithelium contains a massive reflector or tapetum lucidum. Photoreceptor bundles are arranged in parallel rows, the bundles alternating in position from row to row. Each bundle contains about 60 photoreceptors, of which 30 or so are cones. Rod outer segments lie in the scleral half of the outer retinal region of the light-adapted eye. Processes of the pigment epithelium cells extend vitread almost to the external limiting membrane; they envelop the bundles of rods and cones, and a ring of four processes surrounds each bundle. A process contains two kinds of reflecting crystals (composed of uric acid). A large part of the epithelium cell is packed with small disc-shaped crystals (crystallites) enclosed in thin membranes; the tip of the process, in the region of the photoreceptor bundle, contains orderly arrays of small rod-shaped crystals (rodlets). It is suggested that the crystallites form a diffuse reflector backscattering light into the rods; and that the rodlets reflect light regularly from their surfaces into the photoreceptor bundles. In the light-adapted state, rods are enveloped by pigment and crystallites. The organization is compared with that of other fishes that have photoreceptors in bundles (grouped retinae) and tapeta lucida.