Common Comet Star (Linckia guildingii) Care Guide
Linckia guildingii is a circumtropical comet star with one large and several regenerating arms; like other Linckia it is sensitive and needs a mature reef.
Compiled by Aquairi from published sources · Published · Updated
Overview
Linckia guildingii is a sea star of the family Ophidiasteridae with a small disc and usually five long cylindrical arms, occasionally four or six. Colour is variable, often green but also various shades of brown, blue, and dull red; the upper surface looks smooth but is rough to the touch with low, firm nodules. It is frequently sold with one large arm and several small regenerating arms, producing the characteristic comet appearance. WoRMS lists the accepted spelling as Linckia guildingi (Gray, 1840); the knowledge base name Linckia guildingii is retained here.
Taxonomy
- Class: Asteroidea
- Order: Valvatida
- Family: Ophidiasteridae
- Genus: Linckia
- Scientific name: Linckia guildingii
- WoRMS accepted spelling: Linckia guildingi (Gray, 1840)
Habitat
Originally described from Saint Vincent in the Caribbean, the species is circumtropical, occurring in shallow waters of the tropical Pacific, Indian, and Atlantic Oceans and the Caribbean Sea. Recent studies suggest it may comprise several cryptic species.
Tank requirements
- Minimum tank volume: 200 L
- Temperature: 24-26 °C (75-79 °F)
- pH: 8.1-8.4
- Salinity: 1.024-1.026 SG
- dKH: 8-11
- Size: 8-20 cm in diameter
- Lifespan: 5-10 years
- Acclimation: slow drip acclimation required
Diet
Like other Linckia, it grazes on organic films, detritus, and microorganisms across live rock, and requires a mature reef with abundant biofilm to sustain it.
Compatibility
Peaceful and reef-safe with fish. Harlequin shrimp prey on sea stars and should be avoided.
Reproduction
The species reproduces asexually by autotomy, though less frequently than some relatives. A detached arm, the comet, regenerates into a new individual; the madreporite reappears around six months and becomes functional at about ten months.
Linckia guildingii Breeding Guide: Comet Star Autotomy
Overview
Linckia guildingii, the common comet star (also Guilding's sea star or green Linckia), is a sea star of the family Ophidiasteridae reported from shallow tropical waters of the Pacific, Indian and Atlantic Oceans and the Caribbean Sea. In the hobby it appears in tan-pink tones and frequently shows one large arm with several small regenerating arms, the classic comet look.
Reproductive Mode
The species reproduces sexually by broadcast spawning and asexually by autotomy. As with other Linckia, the asexual route via comets is the visible, characteristic mode, while the sexual pathway proceeds through planktonic larvae out of reach of home culture.
Asexual Propagation
L. guildingii sometimes exhibits autotomy, shedding one or more arms. The detached arms, called comets, can move about independently and develop into new individuals, a form of asexual reproduction. Detachment is gradual: most fractures occur about 2.5 cm from the disc, beginning as a small crack on the lower surface that spreads upward; tube feet pull the parts apart over roughly an hour. Damaged tissue heals in about 10 days and a new arm grows over several months.
Sexual Reproduction
Sexual reproduction follows the general asteroid pattern of free-spawned gametes producing bipinnaria and brachiolaria larvae that live as plankton before settling. This dispersal-dependent cycle is not completed in aquaria, so captive increase, if any, comes from comet regeneration.