Lithodid crabs present intriguing questions about evolution of reproductive strategies and developmental evolution of asymmetry. Lopholithodes foraminatus (Decapoda: Anomura: Paguroidea) from British Columbia have a biennial reproductive cycle. Eighteen months of egg-brooding included an embryonic diapause of 12 months. Larvae were released over a long period of up to 3 months due to pronounced differential developmental rate that was apparently not due to differential oxygen availability among brooded eggs. I describe the behaviour, growth, and morphology of 4 zoeal stages, a non-feeding glaucothoe, and early juvenile instars. Approximately 25% of glaucothoe showed reversed asymmetry, which was surprising considering its rarity among field collected adults. Incidence of reversed asymmetry was not affected by rearing temperature or by cheliped removal and did not differ among offspring of reversed and normal females. Lability in the direction of asymmetry during development is enigmatic in light of long-term evolutionary stability of this character among lithodids.
| Identifer | oai:union.ndltd.org:uvic.ca/oai:dspace.library.uvic.ca:1828/2809 |
| Date | 26 May 2010 |
| Creators | Duguid, William |
| Contributors | Page, Louise Roberta |
| Source Sets | University of Victoria |
| Language | English, English |
| Detected Language | English |
| Type | Thesis |
| Rights | Available to the World Wide Web |
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