The discovery of these inconspicuous snails created a storm of interest among the science community and reached worldwide media attention, once its significance was recognised. A closer look at the snails revealed that they had eight pairs of muscles just like the peculiar molluscs called chitons (limpets have only one group of muscles that leaves an imprint in their shells). This was indicating the origin of a segmentation of the body plan, similarly like in chitons. But while chitons have eight shell plates, the newly discovered snails had only one.
Most amazingly, the closest relatives to chitons that looked almost exactly like the new discovery have been living more than 600 millions of years ago. These were only known from fossils and have been thought to be extinct for hundreds of millions of years. Researchers classified them under the name Monoplacophora, and thought they might be a primitive ancestral form from which, later, the modern snails evolved. Today, however, they are seen rather as a side branch than as the ancestors of modern snails.
The scientists were extremely surprised to have found one of these very ancient snail forms that survived up to modern times. Living in depths of about 3500 metres under sea level, this organism obviously remained over millions of years without considerable changes to its appearance. As the last remnant of a once more common group of organisms, it is called a living fossil. Thinking of the fossil Monoplacophoran called Pilina, Dr. Lemche decided to give his finding the species name Neopilina galatheae (the second part of the name was in honor of the expedition).
Like some other living fossils, such as the famous fish Latimeria, Neopilina stems from a habitat type that is remaining relatively unchanged over long time periods, compared to terrestrial habitats: the deep sea. Being too vast and remote to easily reveal all its amazing inhabitants, the deep sea might well offer more surprises to zoologists in the future.
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