Willan's Chromodoris glides gracefully over Indo-Pacific coral reefs, showcasing a striking translucent blue body marked by bold black longitudinal stripes. This sea slug is easily distinguished from close look-alikes by the delicate, glittering white specks that dust its translucent rhinophores and gills. Like many dorid nudibranchs, it advertises its toxicity to predators with these vibrant warning colors while searching for its preferred sponge prey.
Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Key facts
Diet & prey
Dysideid sponges
Cacospongia sponges
Predators
Crabs
Sea spiders
Specialized reef fish
ThreatsReef degradation and ocean warming
HabitatsCoral reefs and rocky drop-offs
Life spanUp to 1 year
Size / weightNot available
Classification
FamilyChromodorididae
SpeciesChromodoris willani
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
Low
Moderate
High
Very high
Why interaction risk is low
Safe to observe at a normal distance.
Responsible observation
Look for the Specks: Distinguish this species from similar blue nudibranchs by looking for tiny white frosting-like specks on its rhinophores and gills.
Do Not Touch: Their delicate bodies are easily damaged by human touch, and they sequester toxins from their sponge diet.
Check Sponge Walls: Search vertical reef walls and crevices rich in sponge growth, where they actively feed.
