[dinosaur] Confuciusornis beak preservation (free pdf)

Ben Creisler
[email protected]

A new paper in open access:

Free pdf:

Amanda Falk, Jingmai O’Connor, Min Wang  and Zhonghe Zhou (2019)
On the Preservation of the Beak in Confuciusornis (Aves: Pygostylia).
Diversity 11(11): 212
doi: https://urldefense.proofpoint.com/v2/url?u=https-3A__doi.org_10.3390_d11110212&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=X0MEqOT7eoAlyw_y5xqtPUC2OUmqZrenN3VLfkzzaiE&s=SAT7UO8WW7-ls_DEeb1Zbk2va7lrpPhQecr_RcXL0qs&e= 
https://urldefense.proofpoint.com/v2/url?u=https-3A__www.mdpi.com_1424-2D2818_11_11_212&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=X0MEqOT7eoAlyw_y5xqtPUC2OUmqZrenN3VLfkzzaiE&s=ug_FA3xZPYRcXXY8Ps2HhTTO1MdsGq2Uz63ilk9lg8c&e= 


The Confuciusornithiformes represent the most stem-ward avian occurrence of
an edentulous rostrum. Although a keratinous beak is widely considered to
have covered the rostrum in confuciusornithiforms, this feature is almost
never preserved, having been previously reported only in the holotype of
Confuciusornis dui and the holotype of Eoconfuciusornis zhengi. This
strongly contrasts with the widespread preservation of the keratinous
sheaths that cover the manual and pedal ungual phalanges. Here, we report
on a third occurrence of a preserved rhamphotheca in a specimen of
Confuciusornis sanctus. We illuminated the preserved traces using
laser-stimulated fluorescence. Similarly to E. zhengi, the rhamphotheca has
been preserved only as a two-dimensional trace, whereas ungual sheaths are
preserved in three dimensions. In contrast to the traces preserved in C.
dui, the rhamphotheca in the discussed specimen of C. sanctus is straight
rather than upturned. This hints towards hidden morphological diversity
within the thousands of Confuciusornis specimens, in which species may be
further differentiated by soft tissue features or behaviors, much like many
living birds, that cannot be detected in fossils, even with exceptional
preservation.