- 著者
- Sancia E. T. van der Meij Magnus L. Johnson Sammy De Grave
- 出版者
- Carcinological Society of Japan
- 雑誌
- Crustacean Research (ISSN:02873478)
- 巻号頁・発行日
- vol.47, pp.89-99, 2018-10-24 (Released:2018-10-24)
- 参考文献数
- 40
- 被引用文献数
- 2
Tropical shallow-water crinoids offer shelter to a diversity of marine life, including various symbiotic palaemonid shrimp species. In this study, the reproductive features of the shrimps Cristimenes commensalis and Pontoniopsis comanthi inhabiting comatulid crinoids are studied and compared. Ovigerous females were collected from the crinoids Anneissia bennetti and Comaster nobilis from Iriomote-jima, Japan. All specimens were examined for the following traits: carapace length, fecundity, embryo volume, brood mass volume and dry weight of the females and the eggs. Cristimenes commensalis produced 15–117 eggs with a volume of 0.04 mm3±0.00, whereas the smaller-sized species P. comanthi produced 12–57 eggs with a volume of 0.02 mm3±0.01. The reproductive output (RO) of C. commensalis was 0.16±0.03, considerably lower than that of P. comanthi at 0.31±0.05. Data is beginning to emerge on the fecundity and reproductive output of symbiotic palaemonid shrimps, although comparisons remain hampered by the general lack of knowledge on their biology in general. Pontoniopsis comanthi has the highest recorded reproductive output so far, despite being the smallest species studied. Our results confirm that inhabiting a sheltered habitat allows symbiotic shrimps to allocate more energy to embryo production than free-living species. Different reproductive strategies are, however, apparent for these species inhabiting the same host species, implying the existence of differential selective forces.
- 著者
- Adam Powell Daniel M. Cowing Susanne P. Eriksson Magnus L. Johnson
- 出版者
- 日本甲殻類学会
- 雑誌
- Crustacean Research (ISSN:02873478)
- 巻号頁・発行日
- vol.46, pp.17-24, 2017 (Released:2017-01-18)
- 参考文献数
- 16
- 被引用文献数
- 8
The Norway lobster, Nephrops norvegicus, is a valuable and commonly exported European decapod crustacean, which experiences stress from point of capture and onward transport. Stressors such as air exposure duration (i.e. emersion period) and air temperature have been studied previously. We investigated whether mortality could be reduced by decreasing road vibrations during transport, and how physiological stress measurements were influenced in a transport simulation experiment, reflecting a typical short road journey along a supply chain. Baseline haemolymph samples were taken from lobsters sampled immediately after commercial capture using static traps (lobster pots). Individuals were emersed for one hour, either immobile or with continuous shaking; the latter to simulate conditions occurring during transport. Both treatments significantly increased Total Haemocyte Counts (THC) and serum glucose, lactate and ammonium concentrations compared to baseline animals. Individuals subjected to continuous shaking showed higher glucose and ammonium concentrations compared to individuals maintained immobile. We conclude that shaking appears to influence the physiological responses of N. norvegicus in addition to the effects of emersion alone, and the reduction of road vibrations (e.g. via simple cushioning) can reduce post-transport mortality.