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A tiny,free back nasty sex videos wrinkly, sack-like sea creature with a huge mouth and no anus could be your ancestor. Saccorhytus was an ancient creature that roamed the Earth 540 million years ago, and according to a new study, it could be one of our earliest known ancestors.

The frightening-looking, millimeter-long organism is thought to be a deuterostome, a category of vertebrates that would evolve into creatures like starfish and acorn worms and even humans. Its image is based on microfossils discovered by researchers in China.

The new study, published in the journal Nature on Monday, shines light on how some of our oldest earthly ancestors may have looked and lived.

"Saccorhytus now gives us remarkable insights into the very first stages of the evolution of a group that led to the fish, and ultimately, to us," Degan Shu, one of the co-authors of the study, said in a statement.

With a "bag-like body," Saccorhytus has a very prominent mouth that could grow in size but likely no anus. It moved around in the mud of ancient seabeds, and what it digested probably also came out of its sizable mouth, according to the study.

The findings are especially notable because the fossils used in the study are incredibly old. That fact could help scientists pin down exactly when certain species branched off from their common ancestors and became distinct.

By looking at the biomolecular markers of certain species, scientists can at least hazard a guess at how long certain species have been on divergent paths from their ancestors, however, the fossil record doesn't necessarily match up with this "molecular clock" data perfectly, according to the statement.

These new Saccorhytus findings might help scientists close the gap in that mismatched history.

"One possibility is that the earliest animals were very small and, in normal circumstances of fossilization, very unlikely to survive," Simon Conway Morris, a University of Cambridge researcher and one of the study authors, told CNN. "In this way, Saccorhytus might give us a glimpse of a long and cryptic history."