Rostanga rubra

Rostanga rubra is a brightly colored nudibranch, exhibiting hues of orange to reddish-orange. Its dorsum is adorned with caryophyllidia, which helps distinguish it from other species within the Rostanga genus. This species is typically found in the Atlantic Ocean and the Mediterranean, having been described from Nice, France, and reported from areas ranging from Norway to Spain, as well as the Canary Islands and Madeira. It inhabits benthic environments and is usually located at depths shallower than 40 meters, with most occurrences recorded at depths around 30 meters or less. Feeding primarily on red sponges, including Ophlitaspongia seriata, Clathria atrasanguinea, and Ophlitaspongia kildensis, Rostanga rubra plays a role in the marine ecosystem by contributing to the control of sponge populations. This nudibranch is a hermaphrodite, meaning it possesses both male and female reproductive organs. During mating, individuals engage in a behavior where they attempt to penetrate each other's body wall, determining dominance in the mating process. Eggs are laid on a substrate, where they develop into a planktonic larval stage before maturing into adults. Encounters with Rostanga rubra during dives can be intriguing due to their distinct coloration and unique feeding habits. Divers may observe them in their natural habitat, often camouflaged among sponges, making them a rewarding find for those exploring the underwater world. The conservation status of this species is currently listed as Not Evaluated.