Echinoidea Community Structure in the Timbul Bone Labunta Sand Waters, Buton Tengah Regency, Southeast Sulawesi

This study aims to determine the types of sea urchins (Echinoidea), the diversity index (H'), uniformity index (E), and dominance index (C) in sea urchins (Echinoidea) in Pasir Timbul Bone Labunta waters, Central Buton Regency. This research is a type of quantitative descriptive research. The determination of stations is carried out using a purposive sampling technique, namely data collection based on the presence of sea urchins (Echinoidea). This research was conducted in April-May 2023 in Pasir Timbul Bone Labunta waters, Central Buton Regency. Observations were made during the day, at the lowest tide, and when sea urchins (Echinoidea) rested in coral crevices or seagrass. The results showed that there were 5 types of sea urchins (Echinoidea), namely Diadema setosum, Echinotrix calamaris, Tripneustes gratilla, Salmacis sphaeroides and Echinometra mathaei. The diversity index at Station I is in the low category, and Stations II and III are in the medium category. Uniformity index at Station I with a low category, Stations II and III with a high category. The dominance index of Station I has a high category, and Stations II and III have a low category index value.