Encyclopedia

Chromodoris dianae   A tiny reef jewel, this nudibranch looks like it’s wearing a delicate, hand-painted gown. Its translucent white body is streaked with irregular black lines and dotted with tiny black spots, each detail adding to its intricate design. The edges of its mantle glow with a bright orange trim, while its frilly gills and antenna-like rhinophores are tipped in fiery yellow-orange, popping vividly against its pale canvas. Size: Up to 40 mm Range: West Pacific; reported from the Philippines, Indonesia, and Borneo Habitat / Depth: Coral reefs and rocky outcrops, typically found at depths of 1–30 m Diet:...

Phyllidiella ocellata   The Ocellated Wart Slug is a small but vividly colored nudibranch, instantly recognizable for its bold orange body accented with black rings and scattered white-tipped tubercles. These “eye-like” spots create a striking pattern that makes the slug appear almost jewel-like against the reef. Its textured, slightly bumpy surface catches the light, while its slow, deliberate movement adds to its mesmerizing presence. This combination of bright orange, deep black, and crisp white makes it one of the most photogenic and easily identifiable nudibranchs in the Indo-Pacific. Size: Up to 70 mm Range: Indo-West Pacific; from the Red Sea...

Chelidonura hirundinina   The Swallowtail Headshield Slug is a striking black sea slug with two long tail-like extensions. Its body is decorated with vivid turquoise, green, and orange lines that run along the headshield and tails, creating a dazzling contrast against the glossy black. As it glides gracefully over sandy reefs, these bright neon-like stripes shimmer in the light, giving it a hypnotic, almost magical appearance. Its movement is smooth and ribbon-like, making it look as though it’s dancing across the seafloor. Size: Up to 40 mm Range: Western Indo-Pacific and Caribbean Sea Habitat / Depth: Found in rocky habitats...

Prostheceraeus roseus   A delicate ribbon of pink flowing through the reef, this flatworm looks like a silky streamer unfurling over algae and rocks. Its body shifts from soft rose to gentle purple, each edge traced with a faint white line, giving it a dreamlike outline. As it glides with smooth, undulating motions, it almost seems to dance across the shallow waters, its bright coloration warning predators to keep their distance while leaving a trail of hypnotic elegance behind. Size: Up to 15 mm Range: Tropical Indo-Pacific Habitat / Depth: Rocky reef habitats, found at depths ranging from 5–50 m...

Phyllidiopsis xishaensis   A tiny marvel of the reef, this nudibranch wears its stripes like a delicate piece of couture. Its pale blue to creamy-white back is streaked with four bold black lines, each ridge rising slightly to create a textured, almost sculpted look. It glides slowly across coral rubble, its lemon-hued rhinophores swaying gently as it explores. This little striped wonder stands out with its precise, elegant patterning and subtle charm. Size: Up to 40 mm Range: Western Central Pacific; the Philippines and the Marshall Islands Habitat / Depth: Coral reef slopes and rocky outcrops, typically found on or...

Rhinecanthus aculeatus   A living masterpiece of the reef, its sandy-beige body is splashed with bold black and electric blue lines, stretching from its curious eyes to the tail, while a sunny yellow patch crowns its dorsal fin like a painter’s final flourish. Laterally compressed and sturdy, it prowls the shallow reef with playful curiosity, snapping its powerful jaws at shelled prey, all while looking like a miniature, mobile abstract canvas gliding through the coral. Size: Up to 30 cm Range: Indo-Pacific; from the Red Sea and East Africa to the Marquesas Islands Habitat / Depth: Coral reefs and sandy...