Abstract
The variations in the body length, swimming legs and some setae of the freshwater cyclopid Acanthocyclops robustus were analysed during an annual cycle in the field, and in laboratory experiments at different culture temperatures. In Lake Créteil. a shallow temperate sand-pit lake, there is a seasonal morphological variation of the setae: the plumose forms were restricted to the warmer season and the spinose ones to colder periods. Contrary to other years, the specific ‘spine formula’ of the swimming legs (3-4-4-4) did not vary during the reference year. In laboratory experiments, both sex and post-embryonic developmental temperatures had an effect on the length of adults. A significant parental effect on body length was detected. Pairs with anomalous spine formulae produced offspring either with anomalous spine formulae or typical 3-4-4-4 formulae. No significant effects of parental culture temperatures, offspring culture temperatures and sex on the total number of spines were found. Modification of plumose into spinose setae did not occur, whatever the offspring developmental temperatures. The results presented here suggest that the alterations of the appendages of the cyclopid A.robustus could be compared to the cyclomorphosis in other zooplanktonic groups, and contribute to our understanding of the role of phenotypic induction in aquatic biology.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.