and the string-like filaments that grow from their eggs.
The new species is described in a research paper published Wednesday in PLoS One by Daniel Stec from the Jagiellonian University, Poland, and colleagues.
Tardigrades are short, plump, eight-legged micro-animals measuring around 0.02 inches long. Sometimes called water bears or moss piglets, the critters pop up everywhere from the deep sea to rainforests. Famed for their resilience, some species can survive extreme radiation, air deprivation and even the vacuum of space. Fossilised tardigrades date back more than 500 million years.
This latest addition to the tardigrade family—which has some 1,200 species—was discovered lurking in a clump of moss. Scientists took 10 individuals back to the lab and bred them to increase their sample.
Eggs and Legs - STEC ET AL (2018)
The team looked at the puffy little creatures under the microscope and analysed their DNA to confirm they were a new species: Macrobiotus shonaicus.
Most similar to certain members of the M. hufelandi group of the tardigrade family, M. shonaicus has a bulging layer on the internal surface of some of its legs, and thin fibers like tentacles that grow from its eggs. The eggs’ solid surface puts the creatures in the persimilis subgroup of the hufelandi complex.
These elongated strings are similar to those found in two other species described since 2015—M. paulinae from Kenya and M. polypiformis from Ecuador. This helped the researchers understand where the newest members fit into the taxonomical tree.
STEC D, ARAKAWA K, MICHALCZYK (2018) PLOS ONE
The new identification brings the number of known tardigrade species in Japan from 167 to 168. Around 20 new species are discovered every year, the authors write. So if you want to track down some tardigrades yourself, they shouldn’t be lurking too far away.
According to Michael Shaw, tardigrade enthusiast and author, you can find the critters in moist clumps of moss or lichen on the trees and bricks of your neighborhood. Just scrape the moss into a petri dish, add water and wait overnight. The next day, you might be able to spot a tardigrade in the dish with just an amateur microscope. Shaw’s article is available here and archived here.