Effects of the nonsteroidal ecdysone mimic RH 5849 on larval crustaceans
β Scribed by Clare, Anthony S. ;Rittschof, Daniel ;Costlow, John D.
- Publisher
- John Wiley and Sons
- Year
- 1992
- Tongue
- English
- Weight
- 556 KB
- Volume
- 262
- Category
- Article
- ISSN
- 0022-104X
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β¦ Synopsis
Abstract
The effects of the nonsteroidal ecdysone mimic RH 5849 on larvae of a crab (Rhithropanopeus harrisii) and the cypris larva of a barnacle (Balanus amphitrite) have been investigated. Larvae were exposed to exogenous RH 5849 in the concentration range of 0.1β10.0 mg/L. The two lowest concentrations tested (0.1 and 1.0 mg/L) accelerated molting of crab zoeae. RH 5849 did not induce premature apolysis. A concentration of 10 mg/L RH 5849 was toxic to zoeae: these larvae underwent apolysis but not ecdysis and subsequently died. Attachment and metamorphosis of barnacle cyprids was enhanced by 10.0 mg/L RH 5849. Increased attachment may be a result of physiological aging of larvae by the ecdysone mimic. Increased metamorphosis is consistent with the stimulatory effect of 20βhydroxyecdysone on this process. RH 5849 was first demonstrated as an ecdysone mimic in insects (Wing, Science, 241:467β469, '88). The present study provides preliminary evidence for a similar action in crustaceans. Β© 1992 WileyβLiss, Inc.
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