Rearing experiments on the amphibian slug Alderia modesta
In: Helgoländer Wissenschaftliche Meeresuntersuchungen. Biologische Anstalt Helgoland: Hamburg. ISSN 0017-9957, more Also appears in:Kinne, O.; Aurich, H. (Ed.) (1967). Vorträge und Diskussionen. Erstes Europäisches Symposion über Meeresbiologie = Papers and discussions. First European Symposium on Marine Biology = Rapports et discussions. Premier symposium européen sur biologie marine. European Marine Biology Symposia, 1. Helgoländer Wissenschaftliche Meeresuntersuchungen, 15(1-4). 669 pp., more |  |
| Abstract | 1. Alderia modesta Lovén lives in enormous numbers onVaucheria-cushions near the supralittoral fringe of the European coasts in salinities from 5 to 40 permil.2. Eggs are produced throughout the year whenever the temperature permits.3. During the warm season one adult animal deposits about 1,000 eggs per day.4. After 4 to 5 days, the larvae hatch and begin their planktonic life. They are planktothrophic and require at least 30 days until they are ready for metamorphosis. Consequently, they contribute considerably to the number of veligers in the plankton; a fact which has hitherto not been realized. Descriptions and figures of the larvae are presented.5. Adults, larvae and eggs are very sensitive to changes in salinity. A differentiation between populations from the western Baltic and from the North Sea must be made. The latter are much more sensitive to fresh water than those from the Baltic. The species Alderia may be regarded as euryhaline, but the individual slugs are stenohaline.6. Reconsideration of the taxonomy of the genus Alderia appears desirable. |
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