Planktotrophic larval development is associated with a restricted geographic range in Lasaea,a genus of brooding,hermaphroditic bivalves |
| |
Authors: | D Ó Foighil |
| |
Institution: | (1) Bamfield Marine Station, VOR 1B0 Bamfield, British Columbia, Canada;(2) Present address: Department of Biological Sciences, Simon Fraser University, V5A 156 Burnaby, British Columbia, Canada |
| |
Abstract: | Members of the intertidal, near-cosmopolitan mollusc genus Lasaea brood their young either to a planktotrophic veliger or crawl-away juvenile stage of development. Developmental mode can be reliably inferred from brood masses and from prodissoconch structure. I have conducted a global developmental survey of this genus based mainly on examination of hundreds of museum lots. With one exception, Lasaea species with a planktotrophic larval development were restricted to the western Pacific. Congeners that lack planktotrophic larvae were found on all continents apart from Antarctica, and also on a large number of oceanic islands. These results indicate that (1) Lasaea species releasing crawl-away juveniles have a markedly greater collective geographic range than congeners with planktotrophic larvae; (2) pelagic larvae are not necessary for long-distance dispersal in this genus; (3) rafting has played a key role in the evolutionary success of the genus Lasaea; (4) cross-fertilizing Lasaea species with feeding larvae are less successful in utilizing chance rafting events to colonize new areas than are congeners lacking these traits. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|