Tardigrade: a new species found in a Japanese parking lot

New species of tardigrade, seen from the front. Credits: Daniel Stec et al

In a Japanese car park, a team of researchers recently discovered a whole new species of tardigrade -the strangest and most resistant organisms on the planet. 

As you may already know, tardigrades (also known as water bears and moss piglets) are incredibly resistant: they can live in the depths of the ocean, they can go without food for years on end and even survive the cold of space, at temperatures close to absolute zero. But not all the species are adapted to such extreme conditions, and some prefer a somewhat more comfortable environment! This is how scientists discovered a whole new species, living on moss on a concrete surface in a Japanese parking lot.

We suppose it’s not really surprising: tardigrades habitually live on moss, lichens and dead leaves. Bioscientist Kazuharu Arakawa from Keio University in Tokyo, who rents an apartment in Tsuruoka above the parking lot in question, was therefore not surprised to find them in a sample of moss taken from the concrete. On the other hand, he didn’t expect to find a whole new species. He and his team used phase contrast light microscopy (PCM) and scanning electron microscopy (SEM) to provide DNA sequences of four molecular markers characterising the new species, Macrobiotus shonaicus, and determining its place in the phylogenetic tree.

New species of tardigrade, Macrobiotus shonaicus, seen from above. Credits: Daniel Stec et al

What differentiates M. shonaicus are its eggs, which have a solid surface and flexible filaments on the exterior, resembling those of two other species recently described, M. paulinae in Africa and M. polypiformis, in South America.

The eggs of the new species of tardigrade, Macrobiotus shonaicus. Credit: Daniel Stec et al

M. shonaicus is in fact the 168th species of tardigrade identified in Japan, among the over 1200 known  species.

You can find all the details of this study in PLOS ONE.