It hid in plain sight for months.
Tardigrades, also known as water bears or moss piglets, are semi-aquatic, micro-animals that can survive in almost any environment.
But because their bodies are so tiny, tardigrades are hard to spot — so researchers have identified very few remains of their fossilized ancestors.
The latest discovery, described by researchers in the journal Proceedings of the Royal Academy B on October 6, is actually a totally new species to science.
Ninon Robin (Harvard/NJIT)
The new tardigrade is called Paradoryphoribius chronocaribbeus, and it measures about half a millimeter in length.
In fact, it’s so tiny that the researchers studied the amber it was eventually found in for months before realizing there was a tardigrade preserved among the other bugs inside.
Here’s what the fossilized water bear looks like up close:
STEVE GSCHMEISSNER/SCIENCE PHOTO LIBRARY/Science Photo Library/Getty Images
Pdo. chronocaribbeus is the most recently living tardigrade fossil ever documented.
This tiny creature lived during the Miocene epoch when a wide variety of land-dwelling mammals roamed the Earth.
The other two tardigrade fossils on record date back 72-93 million years ago to the Cretaceous period, when the dinosaurs ruled.
This relatively young fossil adds another piece to the puzzle of how the resilient creatures evolved to become the hardy minuscule warriors we know today.
“...we saw characters that are not observed in extant species but are observed in the fossils. This helps us understand what changes in the body occurred across millions of years.”
Marc A. Mapalo, lead study author