Berlin Archaeopteryx skull under DGS

The Berlin Archaeopteryx
(MB.Av.101, A. siemensii, Dames 1897) has been traced (Fig. 1) and added to the large reptile tree (not updated yet) where it nests basal to the London specimen and the Enantiornithes, close to the base of the rest of all birds. Thus this fossil is something of a ‘middle-of-the-road’ specimen. Earlier we looked at other Archaeopteryx specimens here, here and here.

Once again
this unique specimen shows why you should not take and combine elements from several Archaeopteryx specimens to create an ‘ideal’ skull.

Figure 1. The Berlin Archaeopteryx, HMN1880, shown here in situ and with DGS tracing and reconstruction. The occiput is segregated to the left as is. Similarly, the palate bones are not reconstructed here.

Figure 1. The Berlin Archaeopteryx, MB.Av.101, shown here in situ and with DGS tracing and reconstruction. The occiput is segregated to the left as is. Similarly, the palate bones are not reconstructed here. They need more examination to determine their outlines. The cranium was crushed. Perhaps it was not as tall in vivo as it appears here in situ. Let me know if you see any mistakes here or if you have pdfs of pertinent literature.

Relatively little
has shifted in this specimen, the classic and complete Archaeopteryx (Fig. 2).

Figure 2. The Berlin specimen of Archaeopteryx (MB.Av.101) with elements traced and the pes reconstructed from visible elements of both feet.

Figure 2. The Berlin specimen of Archaeopteryx (MB.Av.101) with elements traced and the pes reconstructed from visible elements of both feet.

Soft tissue
makes this specimen very exciting. Soft tissue either obscures the clavicle or creates the illusion of a clavicle. The anterior gastralia extend to the coracoids, but, just as in derived birds, a sternum appears to be developing ventral to the anterior gastralia, perhaps unossified at this stage.

Speaking of Archaeopteryx skulls…
I was not aware of the Alsono et al 2004 paper on the extrication and CT scanning of the London specimen skull until this evening. I have made the necessary changes warranted by the additional data (Fig. 3).

Figure 1. The six tested Solnhofen birds currently named Archaeopteryx, Jurapteryx and Wellnhoferia.

Figure 5. The six tested Solnhofen birds currently named Archaeopteryx, Jurapteryx and Wellnhoferia.

References
Dames W 1897.  Ueber Brustbein, Schulter-und Beckengürtel der Archaeopteryx [About sternum, shoulder and pelvic girdles of Archaeopteryx.].  Sitz.-Ber. Akad. Wiss. Berlin 1897 818-834, 3 figs.

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