Padangbai with nudibranch

The bottom-dwelling, jelly-bodied nudibranch.

Some divers say “the more you dive, the smaller you get” … Not that the diver would shrink from diving too much. The thing is that most people, when they start diving, are so overwhelmed by the amazing underwater world that they don’t know where to look first. Usually they look for the big stuff on the first dives, however the more they dive, the more they get intrigued by the little critters.

What is the Nudibranch

You can often see experienced divers scanning the reef in search for little creatures that live on it and sometimes you don’t even know what they are pointing at until they come up to the surface and show you the pictures zoomed in. Among these divers’ favorites are usually the little beauties of the Nudibranch family. Nudibranchs are a group of soft-bodied, marine gastropod molluscs which are some of the most colorful creatures on earth. Although there are exceptions, like to any rule, and you might find pure black, dark brown or even grey ones. There have been about 2,300 species of nudibranchs identified by scientists so far and most of them have extraordinary colors and striking forms.
 
The word "nudibranch" comes from the Latin “nudus” (naked), and the Greek “brankhia” (gills) and it refers to the fact that they don’t have a shell as they get rid of it at a larvae stage. They feed from all sorts of even smaller animals: anemones, tunicates, hydroids, sponges, barnacles and even some other species of nudibranchs!
 
These cute little critters are divided into two main kinds:

  • Dorids are recognised by the branchial plume which forms a cluster on the posterior part of the body.
  • Aeolids have cerata spread across the back, instead of the branchial plume, so they basically lack a plume at the back

 
Nudibranchs are commonly mistaken with flatworm because they look very similar. Make sure you get a comprehensive marine life book guide at your dive center so you write the proper name in your log book after the dives. At our dive center in Padangbai, we are totally addicted to Nudibranchs and when we go fun diving, we just love to look for them. Padangbai is actually the perfect location with plenty of healthy corals and diving conditions suitable even for less experienced divers. Even after many years of diving here, we still manage to find new species that we have never seen before. The catalogue of Nudibranchs seems to be limitless. And so is our fascination with them.
 

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