An extensive survey was conducted from 2019 to 2020 in the sub-tidal regions of the Gulf of Mannar, Southeast coast of India. A total of 20 species of heterobranchs was recorded from the Keelakari group of Islands in the Gulf of Mannar coast using SCUBA gears. Among these, eight species are reported for the first time from the Gulf of Mannar Marine Biosphere Reserve (Aegires villosus, Doriprismatica atromarginata, Glossodoris pallida, Glossodoris rufomarginata, Goniobranchus trimarginatus, Gymnodoris citrina, Hypselodoris infucata, and Tubulophilinopsis gardineri), and one species namely, Aldisa andersoni is a new record to the Indian water. The comprehensive description, morphometric characters and distribution are discussed herewith.

中文翻译：

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印度马纳尔湾 Keelakarai 海岸异分支类（软体动物：腹足纲）的新分布记录

2019 年至 2020 年在印度东南沿海马纳尔湾的潮下带区域进行了广泛的调查。使用 SCUBA 设备从马纳尔湾沿岸的 Keelakari 群岛中记录了总共 20 种异分支类动物。其中，八种报告首次从马纳尔海洋生物圈保护区湾（Aegires villosus，Doriprismatica atromarginata，Glossodoris淡紫，Glossodoris rufomarginata，Goniobranchus trimarginatus，Gymnodoris黄花菜，Hypselodoris infucata和Tubulophilinopsis gardineri），和一个物种，即,阿尔迪萨·安德森尼是印度水的新纪录。综合描述、形态特征和分布在此讨论。