A large bright green slug that is naive to the Green Droplet archipelago. It lives sling the coast line and ventures into the reefs surrounding the island eat algae. It does not have gills but instead stores oxygen in its single lung. It does not swim but creams along the bottom, adhering itself with a thick coating of slime. When it's done feeding it returns to the shelter of the mangrove trees.

Herbivorous marine gastropod.

Bright green.

They have a head with two pairs of feelers. A body with mantle followed by a tail and a 'foot' underneath. The mantle contains the openings to the genitals and anus, as well as the breathing pore/pneumostome. The brimstone has small retractable snorkel that allows the slugs to access fresh air while remaining safe below the surface of the water.

Up to thirteen inches long.

Tropical coastal areas and reefs.

It eats algae that grow in underwater reefs.

Darwin's Slugs. Colony Slugs.

All of Darwin's Slugs descended from unassuming Grey Forest Slug of the Southern Reaches. It somehow reached Green Droplet islands over sixteen thousand years ago. Probably transported there as a cluster of eggs. Either on piece of plant material or by a bird. Being one of the only animals on the island the slugs quickly diversified to fill the available niches.

Many of them developed foul tasting out poisonous slime and bright warning colors to deter hungry sea birds. Many of the slug species developed into herbivores, living in the trees and taking advantage of the abundant foliage. While a few became frugivores or fungivores, while at least one species became detrivores.