Reproduction
Asteroids can regenerate arms and some can reproduce asexually as the central disc divides. In sexual reproduction, asteroids are mainly gonochoristic (having separate sexes), but a few are hermaphroditic. Asteroids usually have two gonads in each arm and a gonopore opening to the oral surface. Gonopores are usually at the base of each arm. Most asteroids are free spawners, releasing sperm and eggs into the water. A few hermaphroditic species brood their young. Spawning is probably nocturnal.
Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate); simultaneous hermaphrodite; sexual ; asexual ; fertilization (External ); viviparous ; oviparous
Although there is generally no parental investment beyond fertilization, a few hermaphroditic species brood their eggs. Brooding species are usually found in environments that are harsh for the larval stage.
Parental Investment: pre-fertilization (Provisioning); pre-hatching/birth (Protecting: Female)
- Brusca, R., G. Brusca. 2003. Invertebrates. Sunderland, Massachusetts: Sinauer Associates, Inc..
- Canada's Aquatic Environments, 2002. "Asteroidea" (On-line). Invertebrates. Accessed January 26, 2005 at http://www.aquatic.uoguelph.ca/inverts/diver/marine/echinodermata/astero.htm.
