Marine life  /  Nudibranchs & sea slugs  /  Marionia
Reviewed 2026-09-06
Species entry

Marionia

Marionia

A soft coral nudibranch with branched cerata that takes the colour of its host.

Size
To about 6 cm
Depth
5–30 m
Habitat
Soft coral on rubble and structure
Active
Day and night
Range
Indo-Pacific
Rarity
Lembeh Strait
4 stars of 5, two or three a season
SP-01
marionia · full body · habitat
4:3 · min 2400px

A dendronotid to about 6 cm with two rows of branched bushy cerata down the back and a fringe of branched processes across the oral veil. Colour follows the soft coral the animal is sitting on, running through pink, red, orange, cream and translucent white, and the branching of the cerata matches the polyp structure closely enough that it is usually found by its outline rather than by its colour.

It feeds on soft corals, and is found on and around colonies on rubble slopes and on structure where current runs. Several species occur in the region and they are not reliably separated in photographs, so a record is normally best kept at the genus. Recorded from about 5 to 30 m.

Where to find:

LocationRarity Best monthsDepthHabitat
Lembeh Strait Indonesia editorial estimate
4 stars of 5, two or three a season
Year-round
5–30 m
Soft coral on rubble and structure
Anilao Philippines editorial estimate
4 stars of 5, two or three a season
Year-round
5–30 m
Soft coral on rubble
Ambon Indonesia editorial estimate
4 stars of 5, two or three a season
Year-round
5–30 m
Soft coral on pilings and rubble
Bali Indonesia editorial estimate
4 stars of 5, two or three a season
Year-round
5–30 m
Soft coral on slopes

Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.

Related species

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