Indonesia is a maritime country with high diversity of marine biota, which one is from Phylum Echinoderms. Echinoderms are known as biota of marine which is are living on corals, sandy, and on the intertidal zone and deep ocean. The intertidal characteristics of Sundak Beach has a suitable structure to echinodems life because there are many corals, but there is many species has not been identified before. The purpose of this research is to know the diversity of echinoderms phylum on the intertidal zone. Sampling was carried out on August, 24th 2019 with purposive random sampling method along the coastal-line in intertidal zone. The result of this research are identified and classified on the each class. Based on the results, the are found species from Echinodea, Holothuroidea, and Ophiuroidea. Species from Echinoidea are Tripneustes gratilla, Echinometra mathaei, Heterocentrotus trigonarius, Diadema antillarum., and Echinothrix calamaris. Holothuroidea namely Holothuria atra. Ophiuroidea namely Ophiotrix fragilis, Ophiocoma scolopendrina, and Ophiocoma erinaceus. The conclusion from this study is the discovery of five species from class Echinoidea, one species from class Holothuroidea and three species from class Ophiuroidea.

Echinoderm is one of the phylum which has high diversity and abundance in Indonesia, especially in Gunung Kidul, Yogyakarta. Sadranan and Slili beach are side by side beach located in Gunung Kidul. This beach is dominated by coral and rocky coral with macroalgae that provide the habitat of Echinoderms. This research is conducted to study the abundance and distribution pattern of Echinoderms in the intertidal zone between Sadranan and Slili beach. Sampling was carried out on Friday, 4 October 2019 at 05.00 p.m. in the intertidal zone using quadrat plot methods. The beach area is 2240 m2 which is divided into 21 plots with 1 x 1 m size. Data analysis was performed by measuring Margalef index (D), Pielou index (e), and Shannon-Wiener index (H’) then analyzing the distribution pattern and habitat parameters. The result shows that the Echinoderms which has the highest abundance is Echinometra mathei with 19 individual founds. The distribution pattern of Echinometra mathei, Stomopneustes variolaris, Heterocentrotus trigonarius, Ophiocoma erinaceus, Macrophiotrix longipeda, Ophiomastix annulosa, and Echinus sp. is clumped. The distribution pattern of Tripneustes gratilla, Diadema antillarum, Echinotrix calamaris, and Ophiocoma scolopendrina is uniform