Impressive images of these alien-like creatures were captured underwater – photographer Cai Songda is a keen diver and did not miss the chance to snap pictures of the unique “aliens”. Here: A Tremoctopus Gracilis in the waters around Anilao, Philippines. (Photo by Cai Songda/Caters News Agency)

A Sydney Aquarium diver uses a vacuum to clean the gravel in the Great Barrier Reef tank as a Ray Shark swims by September 26, 2006 in Sydney, Australia. The Aquarium is undergoing its annual spring clean to prepare for the school holidays using vacuums, along with sea creatures like Sea Cucumbers, Sea Urchins, Cleaner Wrasse Fish and Sea Stars to help complete the job. (Photo by Ian Waldie/Getty Images)

A diver wearing a Santa Claus costume feeds a sunfish to attract visitors at the Hakkeijima Sea Paradise aquarium in Yokohama, suburban Tokyo on December 17, 2014. Christmas attractions will be held till Christmas Day. (Photo by Yoshikazu Tsuno/AFP Photo)

Divers wearing mermaid costumes take part in the first Chinese Mermaid Performance Contest at Atlantis resort on December 21, 2021 in Sanya, Hainan Province of China. (Photo by Luo Yunfei/China News Service via Getty Images)

A diver wearing a Santa Claus costume swims with fishes in a large tank during an underwater performance for the upcoming Christmas celebration at Hakkeijima Sea Paradise in Yokohama, south of Tokyo, Japan on December 1, 2022. (Photo by Kim Kyung-Hoon/Reuters)

Athletes from Australia's Olympic team going to the 2016 Olympics in Rio present their uniforms alongside Brazilian Samba dancer Sashya Jay at an official unveiling ceremony at Sydney's Bondi Beach, March 30, 2016. (Photo by Jason Reed/Reuters)

In this Sunday June 13, 1988 file photo West German police officers arrest an English soccer hooligan who sticks out his tongue. Rioting broke out between some 100 hooligans and the police in downtown Stuttgart, West Germany following the European Soccer Championships match between England and Ireland. England was defeated by Ireland 0-1. (Photo by Kraufmann/AP Photo/File)

Victoria Sinitsina and Nikita Katsalapov, of the Russian Olympic Committee, compete in the team ice dance program during the figure skating competition at the 2022 Winter Olympics, Monday, Feb. 7, 2022, in Beijing. (Photo by Jeff Roberson/AP Photo)