A student's bizarre discovery in a forest has left scientists baffled for over a year.
Jill Fleming, a herpetologist and student at the University of Massachusetts in the US, noticed strange behaviour from an adult toad in a state forest in 2016.
On closer inspection she realised the amphibian had no eyes, nose, jaw, or tongue, meaning it was completely missing its face.
Instead of a head, the top end of the toad was covered in skin with a tiny slit.
After a year of not finding an answer for how the amphibian was alive without a head, Ms Fleming took to Twitter to try again.
"Still puzzled by this find from 2016! An apparently “faceless” toad. Kept hopping into things. Had a small mouth hole - maybe esphogus/glottis (no maxilla or mandible, I think)?" she wrote.
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"It was early spring so I think it must have come out of brumation (hibernation) like this."
The student said her initial thought was that something happened to the toad while it was hibernating.
“For whatever reason, the predator did not finish the job and the toad was able to become active again on that early spring day – amphibians are incredibly resilient," she told the National Geographic.
“I believe the injury happened during hibernation because it seemed to have healed over, which I don't think it would have the opportunity to have done outside the toad's hibernacula."
Ms Fleming said she doesn't believe the toad would have survived for long after she found it.
Some scientists on Twitter said another explanation was a parasitic toadfly that ate its head from the inside.