What a beautiful nudibranch

The opalescent nudibranch (Hermissenda opalescens) is celebrated as one of the most colorful species of sea slug, often described as looking like a "baby ghost leviathan" or a "sliding neon sign" due to its vibrant, iridescent appearance. Filmed off the coast of California, this creature's striking beauty has captivated divers and underwater photographers, with some likening it to creatures from the video game Subnautica. Its dazzling colors are not just for show; they are derived from the pigments of its prey, and some species can even secrete toxins absorbed from their food to deter predators.
The opalescent nudibranch is known for its unique, almost alien appearance, with glowing, horn-like structures that contribute to its otherworldly look.
It is a member of the larger group of over 3,000 identified nudibranch species, which are often called the "Butterflies of the Sea" for their vivid hues and intricate patterns.
Nudibranchs use their tentacles, called rhinophores, to detect prey and navigate their environment, and some, like the opalescent nudibranch, are known to be highly conspicuous in their habitats.
While stunning, these creatures are also potentially dangerous; one Reddit user humorously noted that such a beautiful animal "will probably kill you dead for touching it".