Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Molting growth patterns of the Japanese mitten crab Eriocheir japonica (de Haan) under laboratory-reared conditions

Molting growth patterns of the Japanese mitten crab Eriocheir japonica (de Haan) under... The molting growth pattern of the Japanese mitten crab Eriocheir japonica (de Haan, 1835) was investigated under laboratory-reared conditions. Crabs were individually reared in freshwater for 5 years in a constant temperature room at 23-25°C. The age after metamorphosis and instar number were recorded for each molt, and the intermolt period was calculated for each crab. Carapace width (CW) was measured and the percentage molt increment was calculated. Eleven crabs reached a CW > 10 mm. Each growth curve (age-CW relationship) had two phases in the juvenile stage. Growth rate gradually decreased in the younger phase before changing to nearly constant in the older phase. During the younger phase, the percentage molt increment decreased from 25.0%-38.1% to 6.0%-26.2% (ca. 2-10 mm CW, 1st to 11th instars), and the intermolt period increased from 4-9 days to 40-300 days (ca. 2-20 mm CW, first to thirteenth instars). During the older phase, both parameters became broadly flat but showed marked fluctuations. Crabs reached minimum adult size (ca. 35 mm CW) or the adult stage at 2-4 years after metamorphosis. The instar numbers required by E. japonica to reaching maturity was more than that required by other brachyuran species. The adult stage appeared after the twentieth instar in females, and crabs reached their minimum adult size during the sixteenth to twenty-first instars. After puberty, one female continued molting growth. This suggests that adults could live longer and grow larger in size if they remain in a freshwater environment. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Journal of Crustacean Biology Brill

Molting growth patterns of the Japanese mitten crab Eriocheir japonica (de Haan) under laboratory-reared conditions

Journal of Crustacean Biology , Volume 32 (5): 753 – Jul 7, 2012

Loading next page...
 
/lp/brill/molting-growth-patterns-of-the-japanese-mitten-crab-eriocheir-japonica-j1Zq1VZXJt

References (38)

Publisher
Brill
Copyright
© The Crustacean Society. Published by Brill NV, Leiden
Subject
Ecology
ISSN
0278-0372
eISSN
1937-240X
DOI
10.1163/193724012X649796
Publisher site
See Article on Publisher Site

Abstract

The molting growth pattern of the Japanese mitten crab Eriocheir japonica (de Haan, 1835) was investigated under laboratory-reared conditions. Crabs were individually reared in freshwater for 5 years in a constant temperature room at 23-25°C. The age after metamorphosis and instar number were recorded for each molt, and the intermolt period was calculated for each crab. Carapace width (CW) was measured and the percentage molt increment was calculated. Eleven crabs reached a CW > 10 mm. Each growth curve (age-CW relationship) had two phases in the juvenile stage. Growth rate gradually decreased in the younger phase before changing to nearly constant in the older phase. During the younger phase, the percentage molt increment decreased from 25.0%-38.1% to 6.0%-26.2% (ca. 2-10 mm CW, 1st to 11th instars), and the intermolt period increased from 4-9 days to 40-300 days (ca. 2-20 mm CW, first to thirteenth instars). During the older phase, both parameters became broadly flat but showed marked fluctuations. Crabs reached minimum adult size (ca. 35 mm CW) or the adult stage at 2-4 years after metamorphosis. The instar numbers required by E. japonica to reaching maturity was more than that required by other brachyuran species. The adult stage appeared after the twentieth instar in females, and crabs reached their minimum adult size during the sixteenth to twenty-first instars. After puberty, one female continued molting growth. This suggests that adults could live longer and grow larger in size if they remain in a freshwater environment.

Journal

Journal of Crustacean BiologyBrill

Published: Jul 7, 2012

Keywords: Eriocheir japonica ; instar number reaching maturity; intermolt period; molt increment; molting growth

There are no references for this article.