Hong Kong Baptist University (HKBU) biologists have discovered three new species of coral in the SAR’s waters. The new marine species are hard coral and have not been identified anywhere else in the world.
In a press release, HKBU said that the new species were discovered by Professor Qiu Jian-wen and student Yiu King-fung from the university’s department of biology. They belong to the genus Tubastraea, commonly known as sun coral. The team named the three species Tubastraea dendroida, Tubastraea chloromura and Tubastraea violacea.
Tubastraea dendroida
This species has the typical bright orange colour of most sun corals, but does not grow in clumps like most of its related species. Instead, it has a tree-like structure, which is why it was named ‘dendroida’, meaning ‘tree-shaped’.
Tubastraea violacea
This species is called ‘violacea’ as its polyp wall tissues and skeleton are violet in colour, unlike other sun coral. However, its tentacles are yellow and its corallites (skeletal cups) have a thick wall. There may be colour variants elsewhere, such as a yellow colour variant in New Caledonia in the South Pacific.
Tubastraea chloromura
This coral has an olive green skeletal wall and a circle of yellow tentacles surrounding its mouth. It has therefore been named ‘chloromura’ (‘chloro’ and ‘murus’ meaning ‘green’ and ‘wall’, respectively).
All three coral species are non-reef-building corals and live at depths of between 10 and 30 metres. HKBU biologists say that Tubastraea dendroida and Tubastraea violacea may be found in Japan and the Western Pacific Ocean. Currently, Tubastraea chloromura is only known to inhabit Hong Kong waters.
With the discovery of these species of sun corals, the number of known species in the Tubastraea genus has now increased from seven to 10. The findings of the HKBU team have been will be published in the academic journal Zoological Studies.
This development comes after Professor Qui and his team identified a new species of hard coral and two new species of nudibranch, a type of marine mollusc, in October 2021.
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Header image credits: Hong Kong Baptist University