It should be one of the palaeontological announcements of the decade - the discovery of a fossilised vampire pterosaur that drank the blood of dinosaurs.
But scientists regard the research delivered at the Society of Vertebrate Paleontology (SVP) annual meeting in the US this week as more of a pain in the neck than a serious contribution to scholarly discourse.
David Peters, an American illustrator with no academic training, was due to present evidence that a crow-sized flying reptile from northeast China - Jeholopterus ningchengensis - once drank blood like modern vampire bats and birds.
He said he had been unable to study the fossil itself, but by analysing a photograph on his computer he had identified features missed by the Chinese scientists - he claims to have spotted two long fangs it could have used to bite into the flesh of prey and long claws to help it grip its victim.
"Even Hieronymous Bosch couldn't imagine the terror of one of these locking on to you to milk you for blood," Mr Peters said.
But academic pterosaur experts are united in dismissing his claims. Although Mr Peters' previous studies of flying reptile morphology have reached the pages of the journal Nature and are being given time at the world's leading vertebrate palaeontology meeting, they argue that his new photo interpretation method is highly questionable. As a result, his reinterpretations of pterosaur fossils have been disregarded.
Christopher Bennett, assistant professor at the University of Bridgeport, has devoted a web page to debunking Mr Peters' technique. He said he was surprised to learn that the vampire research would feature at the SVP.
"He has undermined his credibility and has nothing useful to contribute to the discussion," Professor Bennett said.
Dave Martill, reader in palaeobiology at Portsmouth University, said: "I cannot see any of the new things he is finding in his photographs. In my opinion, he is inadvertently creating artefacts that he then interprets as morphological features."
David Unwin, curator for fossil reptiles and birds at Humboldt University, Berlin, added: "The functional explanations of vampirism he puts forward in the abstract are so flimsy that they barely stand up under their own weight."