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Re: Metaves and Coronaves

I believe I've seen it published, but Google can't find that...

But here's something it can find!

Gerald Mayr: A partial skeleton of a new fossil loon (Aves, Gaviiformes) from the early Oligocene of Germany with preserved stomach content, Journal of Ornithology 145, 281 -- 286 (published online 11 August 2004)

The earliest fossil gaviiform is *Neogaeornis wetzeli* from the Cretaceous of Chile (Olson 1992), known from a single tarsometatarsus that resembles the highly derived bone of modern loons. Chatterjee (2002) reported another supposed loon, *Polarornis gregorii*, from the Cretaceous of Antarctica, of which were found the proximal part of the bill and the adjacent distal part of the cranium, parts of the otic region, four vertebrae, a small sternum fragment, a femur, and a proximal tibiotarsus. Despite this very fragmentary preservation, Chatterjee (2002) presented a detailed "reconstruction" of the entire skeleton and a complete skull in which most parts were "constructed by pressing (...) paper pulp into a mold that was sculpted first in clay" (Chatterjee 2002, pp. 128); it is difficult to understand why Chatterjee (1997, pp. 117) described the skull of *Polarornis* as being "fairly intact, beautifully preserved" and figured a drawing of a complete skull with no indication that substantial parts were reconstructed and are not preserved in the specimen.

The phylogenetic position of *Colymboides minutus* relative to *Neogaeornis* and *Polarornis* is uncertain, owing to the incomplete preservation of the Cretaceous taxa. *Polarornis* significantly differs from modern loons in several characters (Chatterjee 2002, p. 133) and, if correctly assigned to the Gaviiformes, may be a synonym of *Neogaeornis* - a possibility already raised by Olson (1992) but not discussed by Chatterjee (2002).

I trusted the drawing in the book from 1997. In the immortal words of Jack Slater... Mighty big mistake.