69 research outputs found

    A bibliography to the mud and musk turtle family Kinosternidae

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    The flathead catfish invasion of the Great Lakes

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    A detailed review of historical literature andmuseumdata revealed that flathead catfish were not historically native in the Great Lakes Basin, with the possible exception of a relict population in Lake Erie. The species has invaded Lake Erie, Lake St. Clair, Lake Huron, nearly all drainages in Michigan, and the Fox/Wolf and Milwaukee drainages in Wisconsin. They have not been collected from Lake Superior yet, and the temperature suitability of that lake is questionable. Flathead catfish have been stocked sparingly in the Great Lakes and is not the mechanism responsible for their spread. A stocking in 1968 in Ohio may be one exception to this. Dispersal resulted from both natural range expansions and unauthorized introductions. The invasion is ongoing, with the species invading both from the east and the west to meet in northern Lake Michigan. Much of this invasion has likely taken place since the 1990s. This species has been documented to have significant impacts on native fishes in other areas where it has been introduced; therefore, educating the public not to release them into new waters is important. Frequent monitoring of rivers and lakes for the presence of this species would detect new populations early so that management actions could be utilized on new populations if desired

    A new species of Anadia (Reptilia, Squamata) from the Venezuelan 'Lost World', northern South America

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    A new gymnophthalmid lizard of the genus Anadia Gray, 1845 is described from the summit of AbakapĂĄ-tepui, BolĂ­var State, Venezuela, between 2200-2242 m elevation. The new species, Anadia mcdiarmidi sp. nov., is endemic to the ChimantĂĄ Massif and seemingly also occurs on AmurĂ­-tepui and Murei-tepui. The new taxon is mainly distinguished from all known congeners by the following combination of characters: body fairly robust, dorsal scales small and quadrangular, middorsal scales 53-57, suboculars large, subequal in size, with sometimes one scale slightly protruding downward between 4th and 5th supralabial, nasal entire, without sub-nostril groove, body uniform beige or greyish to bluish brown in life, devoid of any conspicuous pattern in males, venter immaculate golden grey in life, femoral pores 9-10 on each side in males, preanal pores absent, hemipenis globose, weakly bilobed, bordered by numerous fl ounces (>20) bearing comblike rows of minute weakly mineralized spinules. The presence of a species of Anadia, a primarily Andean genus, on the top of tepuis is of considerable interest to the understanding of the Pantepui biogeography

    A Review of the fossil record of turtles of the clade Pan-Kinosternoidea

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    Turtles of the total clade Pan-Kinosternoidea have a relatively poor fossil record that extends back to the Late Cretaceous (Campanian). The clade is found only in North America during its early history, but dispersed to Central America no later than the Miocene and to South America no later than the Pleistocene. Ancestral pan-kinosternoids were likely aquatic, bottom-walking omnivores or carnivores that preferred low-energy freshwater habitats. The Pan-Dermatemys lineage is often recovered in more fluvial habitats, and some are specialized to feed on aquatic vegetation. Alternatively, many representatives of Kinosternon evolved specializations (e.g., plastral lobe kinesis) that allowed them to successfully inhabit and disperse across more terrestrial habitats such as savannas and floodplains. A taxonomic review of the group concludes that of 42 named taxa, 27 are nomina valida (including two species of the controversial taxon Planetochelys), 14 are nomina invalida and only one a nomen dubium

    An atlas of Michigan fishes with keys and illustrations for their identification.

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    http://deepblue.lib.umich.edu/bitstream/2027.42/56435/1/MP192.pd

    A revision of the lamprey genus Ichthyomyzon.

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    http://deepblue.lib.umich.edu/bitstream/2027.42/56280/1/MP035.pd

    First and most northern occurrence of a thalattosuchian crocodylomorph from the Jurassic of the Isle of Skye, Scotland

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    The Jurassic was a key interval for the evolution of dinosaurs, crocodylomorphs and many other vertebrate groups. In recent years, new vertebrate fossils have emerged from the Early–Middle Jurassic of the Isle of Skye, Scotland; however, much more is known about Skye's dinosaur fauna than its crocodylomorphs. Here we report new crocodylomorph material collected from Jurassic marine deposits at Prince Charlie's Cave on the NE coast of Skye. The specimen is a small cobble containing postcranial elements from an individual that is considerably larger in size than previous crocodylomorphs described from Skye. Based on features of the vertebrae and osteoderms, the specimen is assigned to Thalattosuchia, an extinct clade of semi-aquatic/pelagic crocodylomorphs. Specifically, the sub-circular and bean-shaped pit ornamentation on the dorsal surface of the osteoderms in alternating rows suggests affinities with the semi-aquatic lineage Teleosauroidea. Although the ornamentation pattern on the osteoderms is most similar to Macrospondylus (‘Steneosaurus’) bollensis, we conservatively assign the specimen to Teleosauroidea indeterminate. Regardless of its precise affinities and fragmentary nature, the specimen is the first thalattosuchian discovered in Scotland and is the most northerly reported Jurassic thalattosuchian globally, adding to our understanding of the palaeobiogeography and evolution of this group

    A Review of the Fossil Record of Turtles of the Clade Pan-Kinosternoidea

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    A review of Arctic grayling studies in Alaska, 1952-1982

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    Most information on studies of the Arctic grayling (Thymallus arcticus) in Alaska came from annual progress and performance reports of the Alaska Department of Fish and Game and reports of the Alaska Game Commission prepared before Alaska Statehood in 1959. Only a few reports have been published. Sport harvest, stocking, life history and population estimates are reviewed, and recommendations for further research are offered
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