Over 110 new species from the deep Coral Sea, with 200 or more expected

Numbers from the deep Coral Sea

The Coral Sea Marine Park off northeast Australia covers roughly one million square kilometres. Yet its deep-water fauna had barely been studied.

In late 2025, the CSIRO research vessel RV Investigator set sail.

A 35-day voyage.

Depths of 200 to 3,000 metres.

The team surveyed seamounts, atolls, and unexplored deep reefs.

New species confirmed so far: over 110.

The count keeps growing. Once cryptic species are analysed, the total may exceed 200.

Notable new species

Here are some of the standout discoveries.

Deepwater catshark (genus Apristurus)

A small shark living on the dark seafloor at several hundred metres depth. Sharks are a relatively well-studied group, yet new species still emerge. That is how vast the deep sea remains.

Two new rays (genera Urolophus and Dipturus)

The new Urolophus species bears a butterfly-like pattern. The Dipturus species has a distinctive triangular tail. Both are remarkably rare finds among deep-sea rays.

Jellyfish, isopods, and the sand tiger shark

Fish are not all. Brittlestars, crabs, sea anemones, sponges. New species of isopods and jellyfish were also confirmed.

At the Mellish Seamount, a sand tiger shark (Odontaspis ferox) appeared on the deep-tow camera. A species rarely seen anywhere.

What the researchers say

During the voyage it was incredible to observe plenty of unique, deep-sea creatures in locations from seamounts and atolls to unexplored deep reefs.

— Dr Will White (CSIRO, Voyage Chief Scientist)

Turning specimens into knowledge depends on taxonomic expertise. Discoveries across invertebrate groups are emerging from deeper waters.

— Dr Candice Untiedt (CSIRO)

Taxonomists at the workshops input the species data directly into the Ocean Census Biodiversity Data Platform. This ensures high-quality data is visible to the global community in real time.

— Dr Michelle Taylor (Ocean Census)

Australia's largest-ever marine taxonomy workshops

Collected specimens have been distributed across Australia, now housed in CSIRO's Australian National Fish Collection and state museums.

Dr Will White calls the workshops 'probably the largest taxonomic workshops of marine animals ever undertaken in Australia.' The 110 species are just the opening chapter. As analysis continues, the final count will grow further.

For more on Ocean Census deep-sea surveys, see 'JAMSTEC and Ocean Census explore the Nankai Trough and Shichiyou Seamounts.'

A note from the author: The figure '110-plus species, and still counting' did not feel real at first.

But then I learned that even sharks and rays — relatively large, well-studied animals — included new species. A single research vessel surveying one million square kilometres of ocean: that alone is impressive.