Mauritius’ Most Iconic Nudibranchs

Mauritius is more than just turquoise lagoons and white-sand beaches — it's also home to an incredible diversity of nudibranchs, the flamboyant sea slugs that fascinate underwater photographers and marine life lovers alike.
In this article, we explore the most emblematic nudibranch species found around Mauritius — some easy to spot, others more secretive, and a few exclusive ones that have only recently made their debut on our reefs.

The Thuridilla Twins

• Thuridilla moebii
  Pale green with dots on its mantle.
  
  Thuridilla moebii is a small but eye-catching sea slug known for its vivid blue and orange lines running along a smooth, elongated body. Unlike true nudibranchs, it belongs to the sacoglossan group and feeds primarily on algae. Its streamlined shape and rhythmic, gliding movements give it a graceful presence on the reef, especially in shallow, sunlit areas. Though often overlooked due to its size, its intense colors make it a favorite subject for macro photographers lucky enough to spot it.
  
  
• Thuridilla virgata
  Long body, black and light blue stripes.
  
  Thuridilla virgata is a slender and graceful sea slug, easily recognized by its greenish body adorned with thin, white to bluish longitudinal stripes. Like other sacoglossans, it feeds on algae and is often seen gliding over seagrass beds or rocky reef flats in shallow waters. Its calm movements and sleek, ribbon-like shape give it a refined elegance, making it a rewarding find for divers and photographers who take the time to look closely.

Mauritius' Latest Stars: Costasiella

It’s official — the world’s cutest sea slug has arrived in Mauritius!  The beloved Costasiella, often nicknamed “Shaun the Sheep” for its adorable, fuzzy appearance, has just been discovered on our shores. Long admired by nudibranch lovers and macro photographers worldwide, this tiny sacoglossan was never previously recorded in Mauritius. Its presence opens up thrilling new possibilities for research, observation, and underwater photography — proving once again that our reefs still hold wonderful surprises. Get your cameras ready — this is one celebrity you don’t want to miss!

• Costasiella sp.1
  
  Newly found, beloved for its "Shaun the Sheep" look.
• Costasiella sp.2
  Undescribed but already famous on social media.
  

Where to Spot Nudibranchs in Mauritius

Sandy slopes in the north, reef flats in the southeast, and seagrass lagoons. Night or slow macro dives are ideal.

Why Are Nudibranchs So Fascinating?

From their stunning colors to their strange feeding strategies, nudibranchs are living underwater art.

Dive with Us!

At Panorama Divers, we offer tailor-made macro dives to explore Mauritius' nudibranchs with a passionate guide and underwater photographer.