Isn't she purdy? This ancestor, whose fossil was discovered in August 2016 by an international team of researchers, is known as Saccorhytus coronarius. A study published in January 2017 in the journal Nature describes our long-lost cousin like this: "The bag-like body bears a prominent mouth and associated folds, and behind them up to four conical openings on either side of the body as well as possible sensory structures. An anus may have been absent, and correspondingly the lateral openings probably served to expel water and waste material." In summary, this tiny little thing the size of a grain of sand was basically a large, wrinkly mouth and it probably lacked an anus—one main entrance, no main exit.
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