Linckia laevigata inhabits the tropical waters of the Indian and Pacific Oceans, from the western Indian Ocean to southeastern Polynesia. (Kochzius, et al., 2009; Magsino, et al., 2000; Yamaguchi, 1977)
Individuals have been observed in shallow, multileveled areas in upper zones of sunny reefs and reef fringes in water temperatures from 22 to 26 degrees degrees Celsius. The blue sea star is extremely sensitive to changes in temperature, oxygen level, and pH. (Kochzius, et al., 2009; Magsino, et al., 2000; Yamaguchi, 1977)
Linckia laevigata is characterized by five cylindrical arms with a bright blue or light blue body color and yellow tube feet. Green, pink, and yellow colors have also been observed. Individuals can grow up to 30 to 40 centimeters across. These animals get their color from a blue pigment called linckiacyanin and some accessory yellow carotenoids. The starfish colors vary, depending on the exact ratio and combination of pigments in each individual. (Kochzius, et al., 2009; Magsino, et al., 2000; Williams and Benzie, 1993; Yamaguchi, 1977)
Fertilized Linckia laevigata eggs become larvae after a couple of days. The larvae spend about 28-30 days in the water column before settling onto a hard surface on the reef and metamorphosing into a tiny version of the adult star. The juvenile-to-adult transformation is estimated to take place at about 2 years of age. At this point, they are considered “mini adults” and continue to grow until reaching a length of about 30 centimeters. (Magsino, et al., 2000)
Though the sexes appear indistinguishable when observing this animal externally, the differences can be determined by observing the gonads or by examining the act of spawning when the male and female can be distinguished more readily. During the mating process, gametes are released freely into the water above the animals. Seastars gather in groups when they are prepared to mate to increase the probability of fertilization. If a male and female release gametes in close proximity, the eggs are fertilized. Mating generally occurs in the summer. (Yamaguchi, 1977)
Linckia laevigata spawns between May and August. This species may have a very low level of recruitment. One intensive study found only 10 offspring in one year class. Blue starfish also undergo asexual reproduction, which is the predominant form of reproduction in captivity. During asexual reproduction, the blue starfish divide through their disc, producing clones with identical genetic makeup. (Magsino, et al., 2000; Yamaguchi, 1977)
No parental investment is provided after gametes are released. (Williams and Benzie, 1993)
The blue seastar is known to live as long as 10 years in the wild. The mortality rate is high in captivity because this species requires precise conditions and attention to acclimation. (Magsino, et al., 2000; Williams and Benzie, 1993; Yamaguchi, 1977)
Seastars lack a brain and also do not possess well-defined sensory network. However, they are sensitive to touch, light, the water that surrounds them, and orientation. The pedicellariae of the sea star aid in touch sensation as they function to free the organism of any sediments. The tube feet function as chemoreceptors and are used by the sea star to locate food. ("Blue Starfish", 2009; Deep Sea Waters, 2011)
Linckia laevigata, like other seastars, are opportunistic predators and scavengers. They invert their stomachs and begin to digest their food externally. Food items include dead animals, small invertebrates, and detritus. (Deep Sea Waters, 2011; Reef Reality Series, 2010)
The blue coloring of L. laevigata may warn potential predators of toxicity. Like other seastars, the blue seastar can use autonomy, or self-severance of a limb, to escape predation. Body parts lost to predators are regenerated. (Reef Reality Series, 2010; Rideout, 1975)
The blue sea star is mainly a scavenger, breaking down tissues of dead animals. Linckia laevigata is an obligate host for the limpet Thyca crystallina, which feeds on the hemolymph of the sea star. The shrimp Periclimenes soror, is also parasitic on L. laevigata. (Crandall, et al., 2008)
Blue sea stars are used for decoration and for personal aesthetics (personal aquariums and decorations when they are dried out). They are popular among tourists and in the aquatic life industry. The blue seastar is also being tested as an inexpensive source of potential anti-tumor and antibacterial agents. ("Blue Starfish", 2009; Mojica, et al., 2003)
There are no known adverse effects of L. laevigata on humans.
This species is not listed under any conservation programs. (Reef Reality Series, 2010)
Michelle Baptiste (author), Rutgers University, Ivan Jakimovski (author), Rutgers University, David V. Howe (editor), Rutgers University, Renee Mulcrone (editor), Special Projects.
Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.
body of water between the southern ocean (above 60 degrees south latitude), Australia, Asia, and the western hemisphere. This is the world's largest ocean, covering about 28% of the world's surface.
reproduction that is not sexual; that is, reproduction that does not include recombining the genotypes of two parents
helps break down and decompose dead plants and/or animals
an animal that mainly eats meat
uses smells or other chemicals to communicate
an animal that mainly eats decomposed plants and/or animals
particles of organic material from dead and decomposing organisms. Detritus is the result of the activity of decomposers (organisms that decompose organic material).
a substance used for the diagnosis, cure, mitigation, treatment, or prevention of disease
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
fertilization takes place outside the female's body
union of egg and spermatozoan
having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.
A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.
having the capacity to move from one place to another.
active during the night
an animal that mainly eats all kinds of things, including plants and animals
found in the oriental region of the world. In other words, India and southeast Asia.
the business of buying and selling animals for people to keep in their homes as pets.
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
a form of body symmetry in which the parts of an animal are arranged concentrically around a central oral/aboral axis and more than one imaginary plane through this axis results in halves that are mirror-images of each other. Examples are cnidarians (Phylum Cnidaria, jellyfish, anemones, and corals).
structure produced by the calcium carbonate skeletons of coral polyps (Class Anthozoa). Coral reefs are found in warm, shallow oceans with low nutrient availability. They form the basis for rich communities of other invertebrates, plants, fish, and protists. The polyps live only on the reef surface. Because they depend on symbiotic photosynthetic algae, zooxanthellae, they cannot live where light does not penetrate.
mainly lives in oceans, seas, or other bodies of salt water.
an animal that mainly eats dead animals
breeding is confined to a particular season
reproduction that includes combining the genetic contribution of two individuals, a male and a female
uses touch to communicate
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
2009. "Blue Starfish" (On-line). Accessed November 14, 2010 at http://www.waza.org/en/zoo/choose-a-species/invertebrates/star-fishes-sea-urchins-and-relatives-echinodermata/linckia-laevigata.
Crandall, E., E. Jones, M. Muñoz, B. Akinronbi, M. Erdmann. 2008. Comparative phylogeography of two seastars and their ectosymbionts within the Coral Triangle. Molecular Ecology, 17: 5276–5290.
Deep Sea Waters, 2011. "Blue Sea Star" (On-line). Accessed August 01, 2011 at http://www.deepseawaters.com/deep_sea_blue-sea-star.htm.
Foster, R., M. Smith. 1997. "Linckia Sea Star, Blue (Linckia laevigata)" (On-line). Accessed August 01, 2011 at http://www.liveaquaria.com/product/prod_display.cfm?c=497+528+568&pcatid=568.
Kochzius, M., C. Seidel, J. Hauschild, S. Kirchhoff, P. Mester, I. Meyer-Wachsmuth, A. Nuryanto, J. Timm. 2009. Genetic population structures of the blue starfish Linckia laevigata and its gastropod ectoparasite Thyca crystallina. Marine Ecology Progress Series, 396: 211-219.
Magsino, R., M. Juinio-Meñez, R. Ravago. 2000. Development and application of genetic markers for population structure analysis of the blue coral reef starfish, Linckia laevigata (Linn.) (Echinodermata: Asteroidea). Science Diliman, 12/2: 10-16.
Mojica, E., R. Layson, M. Rodil, C. Deocaris. 2003. Marine invertebrates as source of potential anti-tumor and antibacterial agents. 8th Southern Luzon Zonal R & D Review, DLSU, 1: 1-11.
Reef Reality Series, 2010. "Blue sea star (Linckia laevigata) - Reef reality episode 12" (On-line). Accessed August 01, 2011 at http://www.supergreenme.com/go-green-environment-eco:Blue-Sea-Star--Linckia-laevigata----Reef-Reality-Episode--.
Rideout, R. 1975. Toxicity of the asteroid Linckia laevigata (L.) to the damselfish Dascyllus aruanus (L.). Micronesica, 11: 153-154.
Williams, S., J. Benzie. 1993. Genetic consequences of long larval life in the starfish Linckia laevigata (Echinodermata: Asteroidea) on the Great Barrier Reef. Marine Biology, 117: 71-77.
Yamaguchi, M. 1977. Population structure, spawning, and growth of the coral reef asteroid Linckia laevigata (Linnaeus). Pacific Science, 31/1: 13-30.