Fauna
Plant

Sailor's Eyeball Alga

Valonia ventricosa

Also known as Bubble Alga, Sea Grape, Sailor's Eyeballs

Sailor's eyeball alga forms striking, dark green spherical spheres with a high-gloss sheen that can easily be mistaken for sea marbles or dropped jewels on the reef. Despite growing several centimeters across, each globe is a single multinucleate coenocytic cell anchored to coral rubble or rock by tiny rhizoid outgrowths. When bruised or severed, the protoplasm within organizes into independent cytoplasmic packets that each sprout into new miniature spheres.

MarineUnicellularReef Dweller
Sailor's Eyeball Alga reference1 / 7
(c) Susan Prior, some rights reserved (CC BY), uploaded by Susan Prior · cc-by
—observations
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—peak records
Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Key facts
Diet & preyPhotosynthetic
Predators
  • Emerald Crab
  • Foxface Rabbitfish
  • Sea Urchins
ThreatsReef degradation, ocean warming, and excessive nutrient runoff
HabitatsTropical and subtropical coral reefs, rubble flats, and rocky crevices
Life spanSeveral months to a year
Classification
  1. OrderSiphonocladales
  2. FamilyValoniaceae
  3. GenusValonia
  4. SpeciesValonia ventricosa
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
  • Locating: Peer into shaded reef crevices, dead coral bases, and tidal pools at depths under thirty meters.
  • Handling in aquaria: Avoid popping intact bubbles during maintenance, which can release reproductive spores.
Related species
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Found in Collections

Ecosystem chain

Wetland Territory

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