A microscopic marine animal thought to have died out four million years ago has been found living in seas around New Zealand.
The tiny creature, called Protulophila, was discovered living in small colonies on the mineral armour of tube worms by Museum scientist Dr Paul Taylor. Individuals forming the colony are less than a tenth of a millimetre in size and are relatives of corals and sea anemones.
The discovery marks the rare find of a ‘living fossil’, an organism that is common in the fossil record but is rare today, and often, as was the case with Protulophila, believed to be extinct.
Dr Taylor was collecting fossils in New Zealand on an unrelated project when he spotted the characteristic oval holes made by Protulophila in fossilised tube worms.
The rocks Dr Taylor was examining were less than half a million years old and in the Southern hemisphere. All previous evidence of Protulophila suggested it was only found in Europe and the Middle East and went extinct about four million years ago, after a long history stretching back 170 million years.
‘It’s amazing no-one ever noticed it before, despite it being a popular fossil-hunting site,’ said Dr Taylor. ‘It just needed some serendipity and that I knew something about them from Britain.’
Artist's reconstruction of Protulophila © NIWA.
Prompted by the youth of the rocks, Dr Taylor contacted Dr Dennis Gordon at the National Institute of Water and Atmospheric Research in New Zealand. He described the tube worm to Dr Gordon and asked him to search his more recent collections for evidence of Protulophila holes.
‘The first jar he picked up was absolutely full of Protulophila,’ said Dr Taylor. The jar contained tube worms from Picton, New Zealand, collected in 2008. The fossil creature was alive and well.
However, Dr Gordon found no other worms with characteristic holes in the other jars he searched, suggesting the animal may still be rare and that finding it was a lucky discovery.
Dr Gordon sent samples to the Natural History Museum where Drs Taylor and Andrea Waeschenbach found the creature itself, a small polyp with tentacles that extend out of the holes.
Protulophila was identified as a hydroid, a creature that has two life stages. First, as a polyp, it is anchored to something solid, before budding off and becoming a tiny jellyfish.
There are several microscopic jellyfish in the waters of New Zealand whose polyp stages are unidentified. The team hope that by collecting fresh Protulophila and sequencing its genes they can match it up with one of the jellyfish and be able to describe the whole lifecycle of the animal.
In 1975 Dr Colin Scrutton used evidence from the holes to predict Protulophila would have been a hydroid. He used samples from the Museum’s collection to form his theory, which have been vindicated 40 years later by Museum scientists.