Bergamodactylus wildi- a new name for the basalmost pterosaur, MPUM 6009

Finding higher resolution data
is always a delight. Here DGS and a reconstruction perhaps reveal more accurate data on a skull of a basal pterosaur than direct observation (Fig. 1). You decide.

Figure 1. Begamodactylus skull using DGS to segregate and reconstruct the elements. Lower images from Kellner 2015.

Figure 1. Begamodactylus skull using DGS to segregate and reconstruct the elements. Lower images from Kellner 2015. Note the difference in the tracing of the jugal and the reconstruction of the jugal by Kellner 2015. Some odd things are happening on close examination. Kellner actually traced both jugals there and the quadratojugal is actually the postorbital process of the jugal. The squamosal process of the postorbital is broken so the divergence has been reduced. The teeth are also different. The occiput was not traced originally. A hyoid is in the braincase, overlooked by Kellner.

Kellner (2015)
commented on several Triassic European pterosaurs. Among them, MPUM 6009 was originally described as a juvenile Eudimorphodon by Wild (1978) and later congeneric with the basal anurognathid, Carniadactylus by Dalla Vecchia (2009). Peters (2007) nested this specimen as the basalmost pterosaur, though this reference was not listed. Kellner (2015) reported “no indication that MPUM 6009 is a juvenile.” confirming the assessment here.

Bergamodactylus wildi
is the new name for MPUM 6009 a Late Triassic (Norian) basal pterosaur from Bergamo, Italy. Unfortunately the tracing of the specimen is very vague (Fig. 1). Both jugals are drawn as one and many bones are not identified. This is remedied by DGS, which not only identifies left and right bones, but enables an accurate reconstruction with all parts fitting as in other articulated pterosaurs. Note the twin anterior dentary extensions. Are those teeth? A keratin extension has been hypothesized for other basal pterosaurs. Part of the maxilla ascending process is broken and flipped but repaired above. The posterior process of the left postorbital is broken like a wishbone. Here (Fig. 1) it is repaired to resemble the right postorbital. The occiput is identified along with several hyoids that were overlooked earlier. Does the coronoid have a tall triangular process? Perhaps, but that could also be an ectopterygoid. We’ll have to see about that.

Figure 2. Updated reconstruction of Bergamodactylus to scale with an outgroup, Cosesaurus.

Figure 2. Updated reconstruction of Bergamodactylus to scale with an outgroup, Cosesaurus. Compared to the cranium and declined quadrates, the face appears to be downturned. This only makes sense in a bipedal configuration, as shown.

References
Dalla Vecchia FM 2009. Anatomy and systematics of the pterosaur Carniadactylus (gen. n.) rosenfeldi (Dalla Vecchia, 1995). Rivista Italiana de Paleontologia e Stratigrafia 115 (2): 159-188.
Kellner AWA 2015. Comments on Triassic pterosaurs with discussion about ontogeny and description of new taxa. Anais da Academia Brasileira de Ciências (2015) 87(2): (Annals of the Brazilian Academy of Sciences) Printed version ISSN 0001-3765 / Online version ISSN 1678-2690.
Nesbitt SJ and Hone DWE 2010. An external mandibular fenestra and other archosauriform character states in basal pterosaurs. Palaeodiversity 3: 225-233.
Peters D 2007. The origin and radiation of the Pterosauria. In D. Hone ed. Flugsaurier. The Wellnhofer pterosaur meeting, 2007, Munich, Germany. p. 27.
Wild R 1978. Die Flugsaurier (Reptilia, Pterosauria) aus der Oberen Trias von Cene bei Bergamo, Italien. Bolletino della Societa Paleontologica Italiana 17(2): 176–256.

wiki/Eudimorphodon

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s