Lembeh — 8 September 2025
- Location seen
- Lembeh, Indonesia
- Date seen
- 2025-09-08
Ceratosoma trilobatum
Three-lobed T-bar Nudibranch
© Di Syrett / MacroDivers.com
About this species
- Current scientific name
- Ceratosoma trilobatum
- Common name
- Three-lobed T-bar Nudibranch
- Order
- Nudibranchia - Doridoidea (Dorids)
- Type
- cryptobranchia
- Genus
- Ceratosoma
- Species
- trilobatum
- Average size
- 120 mm
- Colours
- white, orange, purple, red
- Pattern
- spots, edged mantle
- Body shape
- with appendages
- Rhinophores
- horizontal
- Gills
- external gill plume
- Similar species
- Ceratosoma tenue, Ceratosoma gracillimum
Geographic Distribution
Indian and western Pacific oceans.
Identification
Trilobatum's mantle line is usually continuous but in this example it is broken like tenue. Trilobatum has three very obvious lobes - the one protecting the gills and two either side of the gills. Gills are retractile and highly branched. Rhinophores retractile, lamellate.
General Notes
Ceratosoma trilobatum and tenue are of similar size as an adult, both have spots and both have a purple line round the mantle.