Actinotroch larva of Horseshoe worm 4-4-24-1250 This creature is photographed at night on a blackwater dive, off Anilao, in the Philippines, over deep water. Blackwater dives are to photograph the animals and marine life found during the Vertical Migration. This is perhaps the largest migration on Earth and it happens every night in every ocean...when the tiny creatures come up from the depths to feed or be fed upon. In recent years, divers have discovered that they can dive over deep water at night- to photograph these wild looking creatures that otherwise would be hiding in the depths by day- as well as being quite invisible in the light. Most of the animals are quite small, less than the size of your pinky nail. At first I thought this was a type of fish imitating a jellyfish. Turns out to be a type of horseshoe worm ( similar to a feather duster).