DIVERSITY AND DISTRIBUTION OF SOFT CORALS (OCTOCORALLIA: ALCYONACEA) IN THE LOWER SOUTH CHINA SEA

Abstract

Octocorals (Octocorallia: Alcyonacea), which include soft corals and gorgonians are widely distributed in coral reefs of the Indo-West Pacific. However, information and studies about these corals in Malaysian waters are very limited. Therefore, this study aimed at investigating the diversity and distribution of octocorals at the selected islands of Pahang and Johor, East Coast of Peninsular Malaysia, in the lower South China Sea. This study was carried out during the Scientific Expedition UMT Series 1 in August 2015. Two depth zones of shallow (1 to 7 meter) and deep (8 to 20 meter) in each site were surveyed using the photo quadrats technique. Voucher specimens were taken and were morphologically identified up to genus level base on the outer colony form and the shape of the sclerites from the selected parts of the colony. Investigation on light ambient, depth profiles, and type of substrates was also carried out, which may influence octocorals' distribution. A total of 19 genera of octocorals (seven zooxanthellate and 12 azooxanthellate octocorals) were recorded from Pahang and Johor islands. Junceella from the family Ellisellidae was the most common genus as recorded in five out of six surveyed locations. Out of 19 genera recorded in this study, eight octocoral genera were found in Tokong Bahara West, Pulau Jahat, and Tokong Sanggol, which support a rich octocoral fauna among coral communities.