Meet the Costasiella kuroshimae: The real-life underwater 'Pokemon' intriguing scientists worldwide

Seas and oceans constitute the largest unexplored terrain on our planet. This uncharted territory extends limitless opportunities to scientists for exploration, discovery, and innovation. It's vital to acknowledge that investigating our global water bodies paves the way for a deeper understanding of oceanic systems and their workings, which is essential for our survival. Occasionally, not only experts but also ordinary divers chance upon unique and rare underwater flora and fauna. One such finned friend reminds one of the animated character, Shaun the Sheep or a Pokemon! Wondering what this whimsical creature is and whether it poses any harm to us?

This peculiar and attractive creature resides in the aquatic domain, often referred to as the sea sheep or leaf sheep. While its name may lead you to envision a large mammal engulfed in fur, the reality is quite contrary. Its full, somewhat formidable name is Costasiella kuroshimae. It belongs to the family of tiny sea slugs, typically not exceeding two-tenths of an inch. Sea sheep are invertebrates possessing creamy, jelly-like bodies. Their most distinguishing features are their black eyes and dark tentacles which amusingly remind one ...of sheep's ears! These features help Costasiella kuroshimae locate their food and steer clear of threats.

The sea slug Costasiella kuroshimae can be spotted around the shores of Japan, the Philippines, Northern Australia, and Indonesia. The scientific community has been aware of these creatures for only a couple of decades. The knowledge about this sea slug is still sparse. Their lifespan is still a mystery. Yet, one thing is clear: these creatures pose no threat to humans. The Costasiella kuroshimae was first discovered in 1993 in the waters around the Japanese Islands.

People who have been fortunate enough to see these creatures in the flesh are often taken aback by their tiny size. Moreover, their bodies are adorned with distinct green spots that resemble leaves. These are, in fact, branched digestive glands. Intriguingly, most sea sheep are green, but researchers believe they can appear in other colours too.