5 resultados para Dindorf, Wilhelm, 1802-1883.

em Aquatic Commons


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Hypoptopoma inexspectata is diagnosed and redescribed based on the examination of additional material and comparison with its congeners. This poorly known hypoptopomine species is distributed in the Paraguay and Paraná river draínages. Hypoptopoma inexspectata is diagnosable based on the autapomorphy biserial arrangement of anterior snout rostral margin odontodes, laterally extended to limit between second and third infraorbital plates, with dorsally directed dorsad series separated from ventrally directed ventrad series by a narrow odontode-free area, which at the level of first and second infraorbital plates is reduced to a dividing line of the series. The species can be further distinguished by the combination (1) low number of canal-bearing lateral plates (20-22, typically 21), (2) presence of a shield of prepectoral dermal plates, (3) arrangement of abdominal plates in one paired series of 3-5 plates, (4) shorter least interorbital distance 4856% head lengh, (5) larger horizontal eye diameter 17-20% head lengh, and (6) least orbit-nare distance 812% head lengh. Intraspecific variation skull dermal bones, neuracranium and suspensorium bones, dermal plates, adipose fin is reported. (PDF has 20 pages.)

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The findings are presented of a study undertaken to provide baseline information that may be employed to develop a simplified hatchery technique for postlarval feeding of Clarias gariepinus on zooplankton cultured indoors in small aquaria. Three series of experiments were undertaken to identify the type and quantity of organic manure that would produce maximum densities of zooplankton in the shortest time in indoor cultures. Results suggest the possibility of the culture of natural zooplankton populations for use in larval feeding of C. gariepinus fry. Its effective hatchery application would bring about reduction in the unit cost per fingerling and ensure continuous hatchery operations even in the absence of Artemia cysts

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The marine invertebrates of North America received little attention before the arrival of Louis Agassiz in 1846. Agassiz and his students, particularly Addison E. Verrill and Richard Rathbun, and Agassiz's colleague Spencer F. Baird, provided the concept and stimulus for expanded investigations. Baird's U.S. Commission of Fish and Fisheries (1871) provided a principal means, especially through the U.S. Fisheries Steamer Albatross (1882). Rathbun participated in the first and third Albatrossscientific cruises in 1883-84 and published the fist accounts of Albatross parasitic copepods. The first report of Albatross planktonic copepods was published in 1895 by Wilhelm Giesbrecht of the Naples Zoological Station. Other collections were sent to the Norwegian Georg Ossian Sars. The American Charles Branch Wilson eventually added planktonic copepods to his extensive published works on the parasitic copepods from the Albatross. The Albatross copepods from San Francisco Bay were reported upon by Calvin Olin Esterly in 1924. Henry Bryant Bigelow accompanied the last scientific cruise of the Albatross in 1920. Bigelow incorporated the 1920 copepods into his definitive study of the plankton of the Gulf of Maine. The late Otohiko Tanaka, in 1969, published two reviews of Albatross copepods. Albatross copepods will long be worked and reworked. This great ship and her shipmates were mutually inspiring, and they inspire us still.