re Korean pterosaur tracks

[Unwin <h0662eka@rz.hu-berlin.de>]

Regarding recent discussion on the DML of the Korean pterosaur tracks paper by 
Hwang et al (2002). 

For those who have not seen the paper (abstract appended below), the most 
important aspects reported on are the discovery, in South Korea, of many tracks 
made by large and giant pterosaurs that, on the basis of available evidence, 
appear to have been produced by azhdarchids. We also note that the 
morphological diversity of pterosaur tracks is increasing and emphasise the 
remarkable degree of congruency between the pterosaur body fossil and track 
records. 


In a recent commentary on this paper Peters stated: 

<The authors note that I said (Peters 2000) "all pterosaur tracks were made by 
the Ctenochasmatidae?" and then commented, "This seems extremely doubtful?" 
when in reality I said in the conclusion of my paper, "all _known_ pterosaur 
tracks." At the time of that paper's writing, a year before publication, that 
was true. Since one of the authors of the Korean paper has been openly hostile 
to my work here on the DinoList, it's obvious who penned that biased remark.> 

Various papers published in 1997 and 1998 (see ref. list at end of message), a 
year before Peters wrote his paper, subsequently published in 2000, showed that 
the record of pterosaur tracks extended from the Middle Jurassic to the Upper 
Cretaceous, exhibited distinct if modest differences, and included some large 
and giant forms. So, the pterosaur track record, as it was then known in 1998, 
was not consistent with our understanding of Ctenochasmatidae. For example, 
ctenochasmatids were (and still are) not known from the Upper Cretaceous and 
the largest known individuals (holotype of Cearadactylus atrox; Unwin, 2002) 
reach, at most, 3-4 m in wingspan, well short of the large and giant sizes seen 
in the Korean tracks. Moreover, they could not have produced the 
'rhamphorhynchoid' tracks reported by Southwell and Connely (1997). Peters did 
not discuss or mention any of these (or other) incongruencies between tracks 
and ctenochasmatoids, in his 2000 paper.


Later, Peters wrote:

<Finally in the errors and omissions department, the paper compared the Korean 
prints to the supposed "azdarchoid" of Frey and Tischlinger (2000). 
Unfortunately these authors and the Korean footprint authors failed to note 
that azhdarchids have very small unguals, whereas the supposed "azdarchoid" has 
huge unguals. Although similar in many respects, cladistic analysis places the 
"azdarchoid" in with the germanodactylids, a more diverse family than most 
workers realize. >

In the Korean track paper we used the morphology of the pes of the Crato 
azhdarchoid to try to infer one morphological feature of the azhdarchid pes, 
but we did not make any comparisons of the Crato azhdarchoid with the Korean 
prints. Consequently, the size of the unguals in the Crato azhdarchoid was 
irrelevant to the Korean tracks, but may help resolve the identity of this 
pterosaur which, following my inspection of the fossil material, I suspect is 
probably Tapejara, or a closely related form. That various tapejarid skulls 
have been found in the same deposit may not be entirely coincidental. 



Hwang, Koo-Geun, Huh, M., Lockley, M.G., Unwin, D.M. and Wright, J.L. 2002. New 
pterosaur tracks (Pteraichnidae) from the Late Cretaceous Uhangri Formation, SW 
Korea. Geological Magazine, 139 (4), 421-435.

Abstract ­ Numerous footprints of dinosaurs, pterosaurs and birds, together 
with arthropod tracks, have been discovered in the upper Cretaceous Uhangri 
Formation which crops out along the south-western coastline of South Korea. 
This ichnofauna contains the first pterosaur tracks reported from Asia. The 
digitigrade tridactyl manus impressions exhibit features of a typical pterosaur 
hand print. The pes impressions, however, show features that are different from 
pterosaur footprints reported pre-viously: there is no visible trace of 
impressions of individual digits, and the toes are triangular or rounded in 
shape distally without distinct claw impressions. As these features clearly 
distinguish the Uhangri tracks from Pteraichnus and Purbeckopus, we assign them 
to a new genus, Haenamichnus which accommodates the new ichnospecies, 
Haenamichnus uhangriensis. The prints are five to six times larger than those 
of Pteraichnus, and are currently the largest pterosaur ichnites known. T!
hey show virtually no trace of th 5th phalange of the pes, indicating that they 
were made by pterodactyloids; moreover, features of the tracks suggest that 
they can be attributed to azhdarchids, the commonest pterosaur of the Late 
Cretaceous. The longest pterosaur trackway yet known from any track site 
(length 7.3 m) and consisting of 14 pairs of foot impressions, was also found 
in the Uhangri Formation and suggests that azhdarchids, at least, were 
competent terrestrial locomotors. The fossil track site at Uhangri represents 
the first occurrence of the tracks of pterosaurs, dinosaurs and web-footed 
birds all on the same level. This demonstrates that pterosaurs and birds 
visited the same habitat, but the large size disparity suggests that they 
occupied different ecological niches.


Track refs:

Lockley, M.G., Huh, M., Lim, S.-K.,  Yang, S.-Y., Chun, S.-S., & D.M.U. 1997. 
First report of pterosaur tracks from Asia, Chullanam Province, Korea.  Journal 
of the Palaeontological Society of Korea, 2: 17-32. 

Southwell, E. H. & Connely, M. 1997. Preliminary report of a new pterosaur 
track morphotype from the Upper Jurassic Morrison Formation of Wyoming. J. 
Vert. Paleont. 17 (3), 78A.

Unwin, D. M. 1997. Pterosaur tracks and the terrestrial ability of pterosaurs. 
Lethaia, 29: 373-386.

Wright, J.L., D.M.U., Lockley, M.G. & Rainforth, E. 1997. Pterosaur tracks from 
the Purbeck Formation of Dorset, England. Proceedings of the Geologist's 
Association, 108: 39-48. 

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