At last! Two pterosaur specimens that may be conspecific!

Phylogenetic lumpers
like to consider several closely related specimens conspecific and/or congeneric.

Phylogenetic splitters
do the opposite. Rarely are specimens conspecific and/or congeneric in their eyes.

In my studies
of pterosaurs I have never seen two specimens collected at different times and in different places that were conspecific. So I guess that makes me a splitter, but I have to work within the confines of traditional naming paradigms.

In Witton et al. 2015,
I believe I have found a germanodactylid (NMING F15005) pictured in Witton et al. 2015, that may be conspecific with a previously discovered germanodactylid (SMNK PAL 64592, Fig. 1), based on comparative skull anatomy only.

Figure 1. Two germanodactylids that may be conspecific, the more complete SMNK PAL 6592 specimen and the skull only NMIING-F15005 specimen. These two score almost identically in the large pterosaur tree. Can you see the subtle differences?

Figure 1. Two germanodactylids that may be conspecific, the more complete SMNK PAL 6592 specimen and the skull only NMIING-F15005 specimen. These two score almost identically in the large pterosaur tree. Can you see the subtle differences?

The two skulls are almost identical… almost.
The question is… are the differences enough to create a new species? Or not?

So what are the differences in the NMING specimen? 

  1. The anterior dentary is deeper
  2. More teeth are present in the dentary
  3. The antorbital fenestra is longer (further anteriorly)
  4. The anterior jugal is taller and more gracile
  5. The lower antorbital fenestra bar (mx + ju) is more gracile
  6. The quadrate leans further posteriorly
  7. The postorbital appears to be more gracile and lower on the cranium
  8. The base of the orbit is not pointed, but flat creating a larger orbit area

So, are these two specimens conspecific?
Depends if you’re a lumper or a splitter. Do you judge these trait differences as individual variation? or just a little beyond that?

Figure 2. the NMING F15005 specimen with arrows pointing to the upper and lower procumbent teeth that characterize this clade.

Figure 2. the NMING F15005 specimen with arrows pointing to the upper and lower procumbent single teeth that characterize this clade. These teeth are also found in all pteranodontids, dsungaripterids and tapejarids. The blue part of the mandible is also part of the dentary.

I hope you’ll also take note
that at first glance these two skulls appear identical. Putting them side-by-side helps bring out the differences. Always try to make your comparative presentations side by side.

References
Witton MP, O’Sullivan M and Martill DM 2015. The relationships of Cuspicephalus scarfi Martill and Etches, 2013 and Normannognathus wellnhoferi Buffetaut et al., 1998 to other monofenestratan pterosaurs.

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2 thoughts on “At last! Two pterosaur specimens that may be conspecific!

  1. Re lumpers or splitters: Is there not a tendency , in the excitement of the moment in finding new fossil material, to announce the discovery of a new species and examine the matter further and more deeply later on?

  2. Perhaps. Various decades also seem to produce more lumpers, while lately there seem to be more splitters. A lack of appropriate taxon inclusion within phylogenetic analysis is often the fault, one way or the other. To your point, further examination often does comes later.

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