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Marjanovic: Wait for the papers: Hone, Atannasov



Here's why the wait will be disappointing. 
 
In an abstract Atanassov (2001) proposed a new Dockum Group archosaur as a 
pterosaur ancestor, but basal pterosaurs do not exhibit several characters 
cited by him: recurved serrated teeth, sculptured spine tables, a broad 
triangular snout and a high iliac blade. The appressed metatarsus said to 
resemble Dimorphodon weintraubi (figure 6c) would also resemble that of 
Scleromochlus. In my opinion, Atannasov described parts of a bipedal Triassic 
crocodilian. Which should be exciting in itself!
 
Hone's first paper conclusion is as follows [my comments in brackets]:

The results of the re-analyses of the supermatrix suggest that the 
Prolacertiformes should be considered the sister group to the Archosauria. 
[TRUE, if Hone meant the Archosauriformes. Otherwise he is saying 
Prolacertiformes would be closer to Archosauria than Proterosuchus and 
Erythrosuchus.]

The Pterosauria are not closely related to the Prolacertiformes  [TRUE, not 
closely related to Prolacerta and kin, but still closely related to 
Tanystropheus and kin ] and should instead remain among the Archosauria [but 
where?] and probably [with what degree of certainty and on what evidence?] 
among the derived archosaurs [but where? There should be a series of sister 
taxa of descending similarity if a cladogram has been used]. However, the large 
amount of missing data for many taxa [which taxa? so vague is this statement] 
makes it difficult to confirm their true position [and so the card is played. 
Hone doesn't know, but, in the absence of evidence falls back on tradition].

I provided 4 taxa which, when tested in cladistic analysis, each come out 
closer to pterosaurs than any other tested taxon: Longisquama, Sharovipteryx, 
Cosesaurus and Langobardisaurus. Drop any one of them in the pot and see if it 
squeals. 

For that matter, now that I've tested them myself, drop Iguana and Varanus into 
the mix and see where MSNB 6009 (the Milan specimen of Eudimorphodon) comes 
out. Surely there will be no misinterpretation of their bones.

David Peters
St. Louis

PS I also wrote to D. Marjanovic and asked him to send those tracing back for 
reexamination. I have no idea what he is talking about, but I'm sure I will 
when the images jog my memory.