Lembeh — 1 September 2026
- Location seen
- Lembeh, Indonesia
- Date seen
- 2026-09-01
Hypselodoris apolegma
Giant Hypselodoris
© Di Syrett / MacroDivers.com
About this species
- Current scientific name
- Hypselodoris apolegma
- Common name
- Giant Hypselodoris
- Previous genera
- Risbecia
- Order
- Nudibranchia - Doridoidea (Dorids)
- Type
- cryptobranchia
- Genus
- Hypselodoris
- Species
- apolegma
- Average size
- 80 mm
- Colours
- white, yellow, orange, purple, pink
- Pattern
- spots, edged mantle
- Body shape
- Oval
- Rhinophores
- Horizontal
- Gills
- External gill plume
- Similar species
- Hypselodoris bullockii, Hypselodoris variobranchia
Geographic Distribution
Western Pacific Ocean - concentrated throughout the Coral Triangle.
Identification
A large (can reach up to 100mm) and distinctive nudibranch. The dorsum is a deep violet/purple and the mantle edge is white diffusing into the purple. The rhinophores are yellow/orange lamellae clubs protruding from a dark purple stalk. Gills, the same, yellow or orange with a darker purple stalk. Both are fully retractable.
General Notes
There are a number of Hypselodoris with similar colouring (ie purple dorsum and white margin). What distinguishes apolegma is the white mantle edge diffusing into the purple dorsum.