A strange menagerie of creatures living off methane have been found in the darkest depths of the Pacific Ocean.

Spiky white worms and tiny marine snails were filmed picking their way through swaying fields of tube-worms, more than five miles from the surface.

Chinese explorers who visited the area by submarine also found huge beds of clams and large patches of white, snow-like microbial mats.

The waving carpets of worms looked so much like countryside meadows that scientists labelled them “Cotton Field” and “Wintersweet Valley”, while the blanched microbial mats were dubbed “Icy River”.

The creatures are all the more remarkable because they live in complete darkness along major fault-lines where two tectonic plates meet, surviving on hydrogen sulfide and methane produced by seismic activity.

The Kuril–Kamchatka Trench, formed by the Pacific Plate moving beneath the Okhotsk Plate, was the site of this week’s earthquake which sent tsunami waves crashing onto the shores of the US and Japan.

It is not known how the newly-discovered creatures have been impacted by the earthquake.