Kaye, H.R.; Reiswig, H.M. (1991). Sexual reproduction in four Caribbean commercial sponges. III. Larval behaviour, settlement and metamorphosis. Invertebrate Reproduction and Development. 19 (1): 25-35.
Kaye, H.R.; Reiswig, H.M.
Sexual reproduction in four Caribbean commercial sponges. III. Larval behaviour, settlement and metamorphosis.
Larval behaviour, settlement, and metamorphosis were investigated in four Caribbean
commercial sponges, Hippospongia lachne, Spongia barbara, S. cheiris and S. graminea,
using light and transmission electron microscopy. The parenchymella larvae of these
viviparous and gonochoristic species have an average size of 350pm by 420pm when
released. Symbiotic bacteria occur intercellularly in both larvae and post-larvae. Laboratory
behavioural studies demonstrate that free-swimming larvae display directional
swimming with constant lateral rotation and negative phototaxis. Larval settlement occurs
2656 hours after release from the parent and involves the formation of a basal lamella
between the post-larva and substrate. There is no evidence of larval substrate selection by
type or orientation. The canal system begins to form six days after settlement and oscules
are apparent eleven days post-settlement. Available evidence suggests that larval ciliated
epithelial cells are terminally differentiated and do not appear to contribute to formation
of post larva or adult in this group of Porifera.