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Re: Chatterjee's Protoavis

Ian Paulsen wrote:

 I haven't heard much about Chatterjee's Protoavis recently, so I assume
that it is considered invalid, am I correct?

I think it is safer to say that the status of _Protoavis_ is unresolved. There is an opinion contrary to that of Chatterjee's that says that several distinct taxa are represented in the sum total of material assigned to _Protoavis_. At the current time, very few researchers concur with Chatterjee's assessments that (1) all the material belongs to one taxon (although more than one individual is represented), and (2) _Protoavis_ is a true bird, more derived than _Archaeopteryx_.

We need to resolve issue (1) in order to determine if _Protoavis_ is a valid taxon. In other words, does the type material and/or material that can be confidently referred to _Protoavis_ show characters that can be used to diagnose the genus _Protoavis_? Unlike the type specimen of _Archaeopteryx_, the material assigned to _Protoavis_ is disarticulated and poorly preserved. Until the hypodigm for _Protoavis_ is established with more clarity, _Protoavis_ will continue to be excluded from most hypotheses concerning the origin of flight (biomechanical, phylogenetic, or otherwise).

Mark Van Tomme wrote:

I've heard that someone who has checked Protoavis personnaly tell that there's teratosaurian material mixed with some avian like stuff,like the skull for exemple,

By "teratosaurian" material I would guess this someone meant rauisuchian. Others have described the skull and neck to be possibly drepanosaurian in nature. The skulls of drepanosaurids and _Longisquama_ are superficially bird-like - which is why Senter (2004) gave the name "Avicephala" to the clade containing Drepanosauridae and _Longisquama_.

The trend is to ignore this taxon as it's very difficult to obtain authorization to see it.

So I've heard! _Protoavis_ is also ignored due to the possibly chimeric nature of the material. One researcher has been overheard remarking: "It seems to be a fauna, not a taxon".