Spawning season and larval occurrence of blood cockle (Anadara granosa) off the Selangor coast, Peninsular Malaysia

We performed a plankton survey of blood cockle larvae, Anadara spp., and histological observations of the gonads of adult blood cockle, Anadara granosa, in the coastal waters off Sungai Buloh, Peninsular Malaysia from October 2010 to April 2011. The histological observations indicated the main spawning period in both sexes was from November to March. In addition, the occurrence of blood cockle larvae peaked in November and March. Furthermore, a comparison of the distribution between umbo-stage and full-grown larvae suggested the umbo-stage larvae diffused offshore and return to coastal sites where they settle and mature into full-grown larvae.