---
title: Ringed Chromodoris (Goniobranchus annulatus)
scientific_name: Goniobranchus annulatus
common_name: Ringed Chromodoris
taxon: Nudibranch

published: 2023-12-25T10:02:57.477Z
updated: 2025-11-25T13:58:09.000Z
tags: Ringed Chromodoris, Goniobranchus annulatus, Nudibranch, Red Sea, Marine Life, Diving
url: https://redseacreatures.com/taxon/invertebrate/molluscs/nudibranch/ringed-chromodoris
---

# Ringed Chromodoris (*Goniobranchus annulatus*)

**Taxon:** Nudibranch (*Nudibranchia*)  


Goniobranchus annulatus, formerly known as Chromodoris annulata prior to 2012, is a species of sea slug belonging to the family Chromodorididae. Known for its vibrant colors, this shell-less marine gastropod mollusc is classified as a dorid nudibranch.

Measuring up to 100mm in length, Goniobranchus annulatus displays a smooth, pale body adorned with numerous vivid yellow spots, although this characteristic may be absent in certain individuals. The species showcases a distinctive purple ring encircling its gills and another ring around its rhinophores. Additionally, the mantle typically features a purple border. The gills of this nudibranch take on a triangular shape in cross-section.

Initially described from Zanzibar, Goniobranchus annulatus is found in the Red Sea and the Indian Ocean, spanning from the East Coast of South Africa to Thailand. Notably, it is considered a Lessepsian migrant, indicating its recent invasion of the Mediterranean Sea, likely facilitated by the Suez Canal.

---

*Source: [Red Sea Creatures](https://redseacreatures.com/taxon/invertebrate/molluscs/nudibranch/ringed-chromodoris)*
*Updated: November 25, 2025*