Samla riwo

Samla riwo is a small sea slug that typically reaches a maximum length of 20 mm when fully mature. Its body is translucent white and features a delicate lacy pattern of pigmentation, which helps distinguish it from other nudibranchs. The oral tentacles are notably expanded at their tips into spear-like shapes or paddles. The cerata, which are the fleshy projections on its back, have a translucent lower section that reveals a pale peach-colored digestive gland. Above this, a purple band encircles the ceras, ending in a white tip. The rhinophores, which serve as sensory organs on the head, have a bare cylindrical base followed by a club-like structure that contains 16 to 22 closely arranged lamellae, aiding divers in identifying this species. This species was first described from Madang, Papua New Guinea, and is found in various locations throughout the Indo-West Pacific region. It inhabits shallow waters, with all recorded occurrences occurring at depths less than 40 m, and 90% of sightings at depths around 30 m or shallower. Divers may encounter Samla riwo while exploring coral reefs and similar environments, where it is often seen moving slowly among the substrate. While specific details about its diet and reproductive behavior are not provided, nudibranchs generally feed on small invertebrates and may reproduce in a hermaphroditic manner. Spotting Samla riwo during a dive can be an interesting experience due to its unique coloration and anatomical features, which set it apart from other sea slugs. The conservation status of this species is not evaluated, indicating that there is insufficient information regarding its population trends.