Emerald Bubble

Smaragdinella calyculata

Smaragdinella calyculata is a small shelled slug found on rocky shores in the Indo-Pacific, including Hawaii. It features a flat, solid shell that is brownish green with white shades, allowing it to blend in with its rocky environment. The large headshield is wide at the front and narrows to a rounded end, while the shell is partially enclosed by large lateral lobes called parapodia. The animal's chemosensory organs are brown and form a wrinkled ridge on each side of the head, and it has a penial opening located at the right anterior corner of the head. This species is herbivorous, feeding primarily on algae and other bottom-dwelling organisms. Emerald Bubbles inhabit marine benthic zones, typically found in shallow waters near shores, often alongside limpets. They thrive in intertidal areas and coral reefs, where they adhere to rocks and corals. Records indicate that they are usually encountered at depths shallower than 40 meters, with 90% of sightings occurring under 20 meters. Their compact shape and strong foot make them difficult to dislodge from their rocky habitats during low tide. Smaragdinella calyculata is a simultaneous hermaphrodite, which means individuals possess both male and female reproductive organs. Encounters with these slugs during dives can be intriguing, as they often remain stationary, blending into their surroundings. The conservation status of this species is not evaluated, but it is recorded in various dive sites, indicating a relatively common presence in suitable habitats.