A Snorkeler in Nova Scotia Thought This Was a Leaf, but It Was Something Far Weirder

It’s a black blob! It’s a rotten leaf! No, it’s a slug, and a pretty cool one at that.

Snorkelers in Nova Scotia, Canada, have found a number of Elysia chlorotica , commonly known as eastern emerald elysia —elusive slugs that steal the photosynthetic abilities of their food. Studying these creatures could carry implications for various human industries, but they’ve been difficult to study both in the wild and in the lab.

Not a rotten leaf

When snorkeler Elli Ofthenorth, admin of the Facebook group Snorkel 💙 Nova Scotia, first spotted the slug, she “just thought, oh, that’s a rotten leaf, keep going,” she told CBC . It wasn’t until her third time swimming past it that she paid closer attention and realized it wasn’t just a leaf. “I just started yelling, there’s a sea slug here!”