Biologists from Hong Kong Baptist University (HKBU) have discovered in Hong Kong waters a new species of hard coral and two new species of nudibranch, a type of marine mollusc, that have never been identified anywhere else in the world.
The new coral species belongs to the genus Tubastraea, which is commonly known as sun coral due to its bright orange polyps and the circle of tentacles that surround its mouth. The biologists, who were led by Professor Qiu Jianwen of HKBU’s Department of Biology, named the new species Tubastraea megacorallita to reflect the fact that it has the biggest and most structurally complex corallite among the eight recognised Tubastraea species around the world.
Professor Qiu Jianwen (right) and Mr Yiu King-fung, a member of the research team (left), introduce the new coral and nudibranch species.
The HKBU team also discovered two coral-eating species of nudibranch, which are commonly known as sea slugs. Both of the new species belong to the genus Phestilla, which featured only nine recognised species prior to these discoveries. One of them, named Phestilla goniophaga, has a large number of long finger-like, brown and white striped projections called cerata, and a white rounded hump on its back. The other species, named Phestilla fuscostriata, has a white body with brown stripes, and it exhibits excellent mimicry against the colour pattern of its coral host.
“Although 98 species of hard coral have been recorded in Hong Kong, the last time a new coral species was discovered in Hong Kong waters was in 2000,” said Professor Qiu.
The discoveries are a vivid reflection of Hong Kong’s rich marine biodiversity, and the descriptions of the new coral and nudibranch species were published in the academic journals Zootaxa and Zoological Studies, respectively.