Ontogeny of the Marmorkrebs (marbled crayfish): a parthenogenetic crayfish with unknown origin and phylogenetic position
✍ Scribed by Seitz, Robert ;Vilpoux, Kathia ;Hopp, Ulrich ;Harzsch, Steffen ;Maier, Gerhard
- Book ID
- 102890848
- Publisher
- John Wiley and Sons
- Year
- 2005
- Tongue
- English
- Weight
- 615 KB
- Volume
- 303A
- Category
- Article
- ISSN
- 1548-8969
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✦ Synopsis
Abstract
Development, growth, and egg production of the Marmorkrebs (marbled crayfish), a crayfish with parthenogenetic reproduction, uncertain geographic origin, and taxonomic position, was studied under laboratory conditions. Length and weight increments strongly depended on temperature being highest at 30°C, and lowest at 15°C. At 25°C, cephalothorax length and weight increased by 17.5 mm and 1700 mg, respectively, in the course of 150 d, whereas at 15°C these parameters increased by only 7 mm and 100 mg during the same period of time. Photoperiod slightly affected growth at 25°C. During growth experiments, mortality was lower at 20°C compared to higher (25°, 30°C) or lower temperatures (15°C), and lower under short‐day than under long‐day conditions. Females matured early (at an age of 141–255 d, a cephalothorax length of 14–21.5 mm, and a weight of 0.63–2 g) compared to other crayfish species. Reproductive females with a cephalothorax length of between 25–35 mm produced large clutches (up to 416 eggs) and brooding periods varied between 22 and 42 d. In order to establish a staging scheme for Marmorkrebs embryos, embryos were photographed, externally visible ontogenetic events charted, and dissected embryos stained with a nuclear dye. These experiments indicate that their development is virtually identical to that of other crayfish. In conclusion, these results and others show that the Marmorkrebs may be taken as a representative valid model organism for future developmental studies on Crustacea. J. Exp. Zool. 303A: 393–405, 2005. © 2005 Wiley‐Liss, Inc.