Hallucigenia is a very strange creature that lived more than 500 million years ago.
It was given its name because it looked like the product of a hallucination.
Its fossils from the Burgess Shale in Canada were first described by Walcott as a worm.
It was later (1977) redescribed by Conway Morris as a weird headless animal with no modern affinities, which walked on stiff spines.
Then, in 1991, Ramskold and Hou Xianguang realised that the spines were on its back and that its flexible legs bore claws like a velvet worm (Peripatus).
Just last week (24th June 2015) Smith and Caron showed that the creature had a long tubular trunk with eyes and teeth at its end.
The hallucination continues!
However, what has made all invertebrate biologists very happy is to find that the weird Hallucigenia was the ancient relative of their favourite little worm with clawed legs, Peripatus.
And, by a stroke of coincidence, Peripatus belongs to the Phylum Onychophora which means claw bearers.