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Wellnhoferia (the Solnhofen specimen of Archaeopteryx)
Earlier we looked at three other Archaeopteryx specimens and noted that they nested at the bases of distinct clades, the Enantiornithes and the Euornithes. Here we’ll add the Solnhofen specimen of Archaeopteryx (aka Wellnhoferia, Elzanowski 2001, Fig. 1) and a few other taxa to the large reptile tree (601 taxa) to see where they nest.
Figure 1. Wellnhoferia grandis added to the large reptile tree nests at the base of all extant birds, Euornithes, and their extinct relatives, distinct from three other Archaeopteryx specimens. The skull is poorly preserved but these parts, if valid, are preserved in impressions,
Distinct from the other Archaeopteryx specimens,
Wellnhoferia has a shorter tail, a precursor structure to the very short tails of extant birds. This specimen (BSP 1999) nests at the base of the clade that includes Confuciusornis to extant birds (Fig. 2).
Figure 2. Theropod dinosaur subset of the large reptile tree showing the nesting of four Archaeopteryx specimens at or near the bases of several basal bird clades, including the Enantiornithes, the Scansoriopterygidae and the Euornithes.
The Scansoriopterygidae
nesting as basal birds and other notes and issues raised here (Fig. 2) will be considered in later blogs.
Figure 3. The pes of Wellnhoferia as originally figured and as traced and reconstructed here. Contra the original reconstruction, pedal digit 4 does have five phalanges, just like other birds. This is how DGS can be valuable to paleontology.
Unfortunately
Elzaznowski 2001 missed one pedal phalanx from his reconstruction (Fig. 3). The DGS method helped to recover it.
A while back
I wondered if the the several specimens assigned to Archaeopteryx were inappropriately lumped based only on the earlier observation that Solnhofen pterosaurs were likewise inappropriately lumped. This has proven to be true. For all the many genera and species discovered from the Solnhofen lagoons, there is more than one basal bird present. Those who have reconstructed the several specimens have not added them to phylogenetic analyses. Those who do phylogenetic analyses have not added several Archaeopteryx specimen to their studies. This is remedied, to a certain extent, here.
Figure 4. Archaeopteyx specimens to scale. Note the morphological differences. These may be related, but are not conspecific taxa.
I once thought I could add nothing to basal bird studies
since so many workers have published on them. Once again, I am proven wrong. The differences between the specimens are shown to be phylogenetic, not ontogenetic.
Over the next few days
I will portray a few of these basal birds, perhaps with some new insight, as I did earlier with Yi qi, the inappropriately identified dragon wing bird.
References
Elzanowski A 2001. A new genus and species for the largest specimen of Archaeopteryx. Acta Palaeontologica Polonica 46(4):519-532.
Source: https://pterosaurheresies.wordpress.com/2015/11/06/wellnhoferia-the-solnhofen-specimen-of-archaeopteryx/
