Fauna
Invertebrate

Lollyfish Sea Cucumber

Holothuria atra

Also known as Black Sea Cucumber, Black Lollyfish

Lollyfish sea cucumbers continuously vacuum the sea floor, ingesting vast amounts of sandy sediment to digest organic films, bacteria, and microalgae before recycling clean sand back onto the reef. Individuals coat their velvety black bodies with a fine layer of sand grains for camouflage, often leaving only small bare black patches exposed along their backs. When stressed, they can reproduce through transverse fission by simply splitting in half, with both fragments regenerating into complete, functional adults within months.

MarineReef DwellerBenthic
Lollyfish Sea Cucumber reference
Philippe Bourjon / CC BY-SA 3.0 · cc-by-sa
—observations
—countries
—peak records
Least ConcernConservation statusIUCN Red List categoriesLCNTVUENCREWEXLeast ConcernRed List categories, explained →
Key facts
Diet & preyDetritus, Benthic Microalgae, Bacteria
Predators
  • Triton's Trumpet
  • Loggerhead Sea Turtle
  • Titan Triggerfish
ThreatsOverharvesting for the trepang trade, habitat degradation, and ocean warming
HabitatsShallow coral reefs, outer lagoons, seagrass beds, and sand flats
Life span5–10 years
Classification
  1. OrderHolothuriida
  2. FamilyHolothuriidae
  3. GenusHolothuria
  4. SpeciesHolothuria atra
Range & activity
Range data is not available yet.
Safe observation
Interaction riskHigh
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is high
Safe to observe at a normal distance while snorkeling or diving.
Responsible observation
  • Spotting Guide: Look for a smooth black body dusted with sand, leaving small bare dark patches.
  • Reef Etiquette: Never pick up or squeeze sea cucumbers, as handling strips their protective mucus layer.
Related species
Keep collecting in Fauna

Found in Collections

Ecosystem chain Pro

Coral Currents

Lollyfish Sea Cucumber is found in this collection. Identify it in Fauna to fill this slot and continue your progress.

Unlock to track progress

Continue in the app
Help improve the field guideSomething wrong?

Report a name, category, or profile issue for review.

Checking your Fauna account…