Sea butterflies aren't typical marine gastropods. These free-floating creatures have evolved unique physical features over time. 

Often delicate and transparent, their shells are mostly non-existent or greatly diminished in some families. Their snail foot has evolved significantly into wing-like lobes that help them navigate the ocean’s currents.

Its shells are made of calcium with varying shapes, from needle-like to globular. These structures measure less than half an inch, invisible to the naked eye.

Recognized as one of the most populous gastropod species, Sea Butterflies play a crucial role in the oceanic food chain and carbon cycle. Their size masks their immense ecological influence4 beneath our oceans' surface.