Fauna
Invertebrate

Multicolored Knobbed Sea Star

Pentaceraster mammillatus

Also known as Knobbed Sea Star, Horned Sea Star, Tuberculate Sea Star

Multicolored knobbed sea stars glide across sandy lagoons and shallow reef flats using hundreds of hydraulically driven tube feet. Their thick, leathery bodies are studded with prominent conical tubercles that display striking individual color patterns ranging from brick red and orange to mottled tan and grey. As opportunistic scavengers, they evert their stomachs over seagrass beds and coral rubble to externally digest biofilm, sponges, and decaying organic matter.

MarineReef DwellerInvertebrate
Multicolored Knobbed Sea Star reference1 / 2
(c) Emanuele Santarelli, some rights reserved (CC BY-SA) · cc-by-sa
—observations
—countries
—peak records
Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Key facts
Diet & preyAlgal turf, Encrusting sponges, Benthic detritus
Predators
  • Triton's trumpet
  • Harlequin shrimp
  • White-spotted puffer
ThreatsCurio trade harvesting, coastal runoff, seagrass loss
HabitatsSeagrass meadows, coral reef flats, sandy lagoons
Life span15–35 years
Classification
  1. OrderValvatida
  2. FamilyOreasteridae
  3. GenusPentaceraster
  4. SpeciesPentaceraster mammillatus
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Safe to observe at a normal distance.
Responsible observation
  • Keep Submerged: Never lift sea stars out of the water, as exposure to air can trap air pockets inside their water vascular system.
  • Watch Your Footing: Avoid stepping on sandy shallows and seagrass patches where individuals rest camouflaged under shallow water.
Related species
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