Linckia laevigata inhabits the tropical waters of the Indian and Pacific Oceans, from the western Indian Ocean to southeastern Polynesia.

Biogeographic Regions: oriental ; australian ; indian ocean; pacific ocean

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.

Range mass: 11 to 16 g.

Range length: 30 (high) cm.

Other Physical Features: ectothermic ; heterothermic ; radial symmetry

Sexual Dimorphism: sexes alike

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.

Range elevation: N/A (high) m.

Range depth: 60 to <1 m.

Habitat Regions: tropical ; saltwater or marine

Aquatic Biomes: reef

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.

Animal Foods: aquatic or marine worms; other marine invertebrates

Plant Foods: algae

Other Foods: detritus

Primary Diet: carnivore (Eats other marine invertebrates, Scavenger ); omnivore ; detritivore

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.

Ecosystem Impact: biodegradation

Commensal/Parasitic Species:

• Thyca crystallina
• Periclimenes soror

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.

Known Predators:

• Pufferfishes
• Triton shells, Charonia spp.
• Harlequin shrimp, Hymenocera spp.
• Sea anemones
• Damselfish, Dascyllusaruanus spp.

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.

Communication Channels: tactile ; chemical

Perception Channels: tactile ; chemical

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.

Development - Life Cycle: metamorphosis

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.

Range lifespan

Status: wild: 10 (high) years.

Typical lifespan

Status: wild: 10 (high) years.

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.

Mating System: polygynandrous (promiscuous)

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.

Breeding interval: The blue sea star usually spawns once a year.

Breeding season: The blue sea star usually spawns from May to August.

Range gestation period: 28 to 30 days.

Range age at sexual or reproductive maturity (female): 2 (high) years.

Range age at sexual or reproductive maturity (male): 2 (high) years.

Key Reproductive Features: seasonal breeding ; sexual ; asexual ; fertilization (External ); broadcast (group) spawning

No parental investment is provided after gametes are released.

Parental Investment: pre-fertilization (Provisioning)

This species is not listed under any conservation programs.

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

There are no known adverse effects of L. laevigata on humans.

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.

Positive Impacts: pet trade ; source of medicine or drug