Invertebrate
Flat Sea Star
Astropecten articulatusAlso known as Royal Starfish, Marginate Sea Star
Royal starfish display a striking contrast of deep royal blue or purple central discs bordered by bright orange marginal plates lined with fine spines. Native to the western Atlantic Ocean, these active predators travel over sandy or muddy seafloors consuming small marine invertebrates whole. Unlike many other sea stars, they lack suckers on their tube feet, using pointed feet instead to glide swiftly across soft benthic substrates.
MarineInvertebrateColorful
—observations
—countries
—peak records
Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Diet & preyClams, Snails, Small Crustaceans
Predators
- Bottom-feeding Fish
- Crabs
- Gulls
ThreatsBottom trawling, coastal pollution, habitat destruction
HabitatsSandy and muddy seafloors, subtidal zones, shallow shelf waters
Life span5–10 years
Classification
- OrderPaxillosida
- FamilyAstropectinidae
- GenusAstropecten
- SpeciesAstropecten articulatus
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Safe to observe at a normal distance.
Responsible observation
- Observing in Habitat: Look for distinct star shapes half-buried in soft sand near shallow reefs or docks.
- Handling Advice: Avoid removing sea stars from water, as air exposure causes rapid distress and tissue damage.
- Photography Tip: Use natural underwater light to capture the vivid contrast between the purple body and orange margin.
Frequent Companion (c) Steven Joyner, some rights reserved (CC BY), uploaded by Steven Joyner · cc-by
Co-occurring Species (c) Tom Kennedy, some rights reserved (CC BY) · cc-by
Close Relative (c) Pauline Walsh Jacobson, some rights reserved (CC BY) · cc-by
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