The ornate eagle ray or reticulate eagle ray (''Aetomylaeus vespertilio'') is a species of large stingray of the family Myliobatidae. Like other rays, the ornate eagle ray is

ovoviviparous Ovoviviparity, ovovivipary, ovivipary, or aplacental viviparity is a "bridging" form of reproduction between egg-laying oviparity, oviparous and live-bearing viviparity, viviparous reproduction. Ovoviviparous animals possess embryos that develo ...

. ''Aetomylaeus vespertilio'' are estimated to have a low fecundity similar to other myliobatids. They have a generation length of 15 years, and can grow as old as 24 years. They are a predatory cartilaginous fish, preying mostly on small

invertebrates Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordate subphylum ...

, polychaete worms, and some

echinoderms An echinoderm () is any animal of the phylum Echinodermata (), which includes starfish, brittle stars, sea urchins, sand dollars and sea cucumbers, as well as the sessile sea lilies or "stone lilies". While bilaterally symmetrical as larv ...

. They have earned the nickname "unicorn of the sea" due to how rarely they are spotted in the wild.

Appearance

''Aetomylaeus vespertilio'' has a maximum size of around 240 cm in disc width and a clearly distinct pattern of reticulate dark lines and rings on its back. If the extremely long tail is unbroken, it can considerably add to the maximum body length of 4m. Lacking a spine on the tail, it is deemed harmless to humans.

Distribution

''Aetomylaeus vespertilio'' can be spotted up to 110 meters deep along the coasts of

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

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Palau Palau, officially the Republic of Palau, is an island country in the Micronesia subregion of Oceania in the western Pacific Ocean. The Republic of Palau consists of approximately 340 islands and is the western part of the Caroline Islands ...

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, and

Thailand Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...

. Despite the wide range it can be spotted at, it is rarely observed, and has been suspected to have had a large population decline within the past three generations. Currently, this species is considered

Critically Endangered An IUCN Red List critically endangered (CR or sometimes CE) species is one that has been categorized by the International Union for Conservation of Nature as facing an extremely high risk of extinction in the wild. As of December 2023, of t ...

by the

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

. There have been fewer than 60 confirmed sightings of ''Aetomylaeus vespertilio,'' giving it the nickname 'the unicorn of the sea.'

Threats and Conservation Efforts

Although ''Aetomylaeus vespertilio'' was once common, they are now considered rare in areas such as the Gulf of Thailand. The largest threats they encounter are demersal fisheries, which are used frequently in the areas they live in. When caught, they are mostly retained and sold in fish markets. No species-specific conservation measures have taken place, but there are more regulations being placed on demersal fisheries to limit the amount of Myliobatidae being caught.

References

Sources

* * McGrouther, M. 2018, Australian museum website
Ornate Eagle Ray, Aetomylaeus vespertilio (Bleeker, 1852)
*

External links

Species Description of Aetomylaeus vespertilio at www.shark-references.com
* {{Taxonbar, from=Q4550289 Aetomylaeus Fish described in 1852 Taxonomy articles created by Polbot