Vanishing of an isolated population of thick-clawed crayfish Astacus pachypus (Crustacea: Decapoda: Astacidae) in the Sevastopol Bay (Crimean Peninsula, Black Sea)
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منابع مشابه
Comparative Ultrastructure and Carbohydrate Composition of Gastroliths from Astacidae, Cambaridae and Parastacidae Freshwater Crayfish (Crustacea, Decapoda)
Crustaceans have to cyclically replace their rigid exoskeleton in order to grow. Most of them harden this skeleton by a calcification process. Some decapods (land crabs, lobsters and crayfish) elaborate calcium storage structures as a reservoir of calcium ions in their stomach wall, as so-called gastroliths. For a better understanding of the cyclic elaboration of these calcium deposits, we stud...
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Lunar-Rhythmic Molting in Laboratory Populations of the Noble Crayfish Astacus astacus (Crustacea, Astacidea): An Experimental Analysis
Juvenile noble crayfish, Astacusastacus (Crustacea, Astacidea) in the second year of age were kept in the laboratory for a twelve-month period under continuing "summer conditions" (LD 16:8, 19°C). Molting processes in this population could be synchronized by artificial moonlight cycles. Peaks of exuviations occurred at "new moons". Males showed a slightly higher degree of synchronization than f...
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Dietary cholesterol has been shown to be essential for several crustacean species. However, cholesterol requirement of narrow-clawed crayfish has not been reported. Therefore, a 12-week feeding trial was conducted to determine deitary cholesterol requirement of narrow-clawed crayfish. Juvenile crayfish with an average body weight of 13.8±1 g mean weight were intensively stocked in an indoor rec...
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A new species, Cherax warsamsonicussp. n., endemic to the Warsamson River drainage, in the western part of the Kepala Burung (Vogelkop) peninsula, West Papua, Indonesia, is described, figured and compared with its closely related species, Cherax misolicus Holthuis, 1949. The new species may be easily distinguished from C. misolicus by the shape of the rostrum, absence of setae on the rostrum, t...
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ژورنال
عنوان ژورنال: rej
سال: 2016
ISSN: 0136-006X
DOI: 10.15298/arthsel.25.1.05