Macrocollum enters the LRT

Figure 1.Macrocollum reconstructed alongside various bones From Müller et al. 2018.

Figure 1.Macrocollum reconstructed alongside various bones From Müller et al. 2018.

Macrocollum itaquii (Müller et al. 2018; CAPPA/UFSM 0001b; early Norian, Triassic, 225 myap; 3m in length) was originally considered a member of the “Unaysauridae [which] differs from all other sauropodomorphs by a substantial cranial expansion of the medial condyle of the astragalus. In addition, a promaxillary fenestra is also unique for the group of sauropodomorphs.” Here, in the LRT,  Macrocollum nests with Efraasia, but shares many traits with Massospondylus. That matches the original phylogenetic analysis.

The species is known
from three closely associated specimens demonstrating gregarious behavior. The skull is quite small relative to the neck and rest of the body, even by sauropodomorphi standards. Atypically manual digit 3 is about as long as digit 2.

References
Müller RT, Langer MC and Dias-da-Silva S 2018. An exceptionally preserved association of complete dinosaur skeletons reveals the oldest long-necked sauropodomorphs. Biol. Lett. 14: 20180633. http://dx.doi.org/10.1098/rsbl.2018.0633

wiki/Efraasia
wiki/Macrocollum

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 )

Google photo

You are commenting using your Google 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 )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.