Sometimes we get so caught up in the search for aliens up above we forget there is still a largely unexplored world of extraordinary life down below. So when an opportunity to glimpse some of the secrets of the deep comes along, we jump at the chance to share them with you.

This latest look at life under the waves comes courtesy of the Underwater Photography Guide’s Ocean Art Contest. Now in its seventh year, the 2018 winners have been announced, and they are rather incredible to behold.

From ocean giants to ludicrously tiny specimens, the weird and wonderful have been captured – some graceful and dignified, others perhaps not quite so photo-ready – by some of the best underwater photographers in the world.

Sixteen different categories, from the technical Wide-angle and Macro to Marine Life Behavior and Underwater Art, ensured a wide range of photographic styles and skills. Nudibranchs even got their own category, because frankly, those dudes are so strange-looking and diverse, they deserve it.  

With prizes totaling $80,000, photographers from over 70 countries entered and the quality of submissions this year was the best yet, according to the organizers.

“This year’s outstanding underwater images in the Ocean Art Underwater Photo Competition continue to raise the bar for underwater photographers,” Underwater Photography Guide publisher Scott Gietler said in a statement announcing the winners.

Best in Show was won by Duncan Morell for his “Courting Devil Ray Ballet”, submitted in the Marine Life Behaviour category. Caught mid-wooing, the rays are beautiful in their movements, however giant devil rays, which can reach up to a 5-meter (16-foot) wingspan, are listed as endangered due to being unwitting victims of bycatch by large fisheries, so this behavior documented is of scientific interest as well as aesthetic.

And in case you were wondering just how "giant" these rays can get...

Not to be outdone in the dramatic stakes, this crocodile reminds us that having been around for 200 million years, they easily outlived the dinosaurs. 

Life under the waves offers up some truly weird, wonderful, and sometimes surprisingly cute, creatures.

Even deep-sea beasties manage to show off personality and whether they are happy or not to have their photo taken.

New this year was the Underwater Art category, won this year by Bruno Van Saen for this snazzy shot of a '"disco" nudibranch. 

And finally, one of our favorites, not least because we don't know how long corals like this will be around to be photographed. You can check out the rest of the winners and entries over on the Underwater Photography Guide website.