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Re: new papers in Acta Geologica Sinica: Ningchengopterus



With regard to Ningchengopterus, and lots of other new pterosaurs, it would be very helpful for the authors to

1. spend more time delineating the skull and other elements, rather than calling it quits after simply broadly outlining of the resulting roadkill.

2. create detailed reconstructions of their finds and compare them to similar reconstructions of closest known sister taxa to assure and demonstrate affinity.

2a. This is especially pertinent in the case of potential 'babies' or 'juveniles' because there's this hypothesis floating around (Wellnhofer, Jouvé, Bennett and others) that states the juveniles don't have to look like the parents.

2b. in cases of reported ontogenetic change in pterosaurs we need to reexamine those three pterosaur embryos and compare them to adult taxa to see exactly what does change during ontogeny. Those are the only young pterosaurs for which an exact ontogenetic age is known. Right now, there are no established rules we can follow. These specimens can establish a baseline of data in three clades.

3. quit relying on a few long bone proportions alone. More tests and comparisons are needed from other, more revealing and apomorphic portions of the anatomy.

4. recall the ironically prescient words of David Unwin 2004 in his book 'The Pterosaurs from Deep Time' in which he wrote: "Ås a rule, this means that juveniles tend to be uncommon in the vertebrate fossil record, and individuals at very early states of growth (newborn or even prenatal) are rare or unknown–except, oddly enough, in pterosaurs."


David Peters davidpeters@att.net


Junchang LÜ. 2009. A Baby Pterodactyloid Pterosaur from the Yixian Formation of Ningcheng, Inner Mongolia, China. Acta Geologica Sinica, Volume 83 Issue 1, 1-8.


ABSTRACT
A new baby pterodactyloid pterosaur with soft tissue preserved, Ningchengopterus liuae gen. et sp. nov., is erected based on a nearly complete skeleton with a skull. It was characterized by the skull, slightly longer than the combined length of the dorsal and sacral vertebrae; 50 teeth (including upper and lower jaws); short mid- cervical vertebrae; the humerus and the scapula, equal to that of the wing metacarpal in length; the ulna and the femur, equal to that of the first and third wing phalanx in length, respectively. The similar ratio of the wing phalanx 2 to wing phalanx 1 of Ningchengopterus and Eosipterus implies that Ningchengopterus may be close to the ctenochasmatid pterosaur. However, it may also imply that the isometrically growing of the first two wing phalanges exists among some pterosaurs.