Eoraptor clavicles: Where did they go?

Figure 1. There is a strap of bone near the anterior coracoid, but it was correctly identified as a distal rib.

Figure 1. This is Eoraptor in situ. There is a strap of bone near the anterior coracoid, but it was originally correctly identified as a distal cervical rib.

Eoraptor lunensis (Sereno et al. 1993) is a basal phytodinosaur, derived from a sister to Herrerasaurus, basal to Pampadromaeus and Leyesaurus.

Eoraptor has no clavicles.
Ancestors had clavicles. At least (= at present only) two descendants, Massospondylus (Yates and Vasconcelos 2005) and Psittacosaurus had tiny clavicles. So what happened to the clavicles in Eoraptor? Did they leave a trace of their disappearance?

Figure 2. Eoraptor does not preserve clavicles, but it does appear to preserve clavicle anchors.

Figure 2. Eoraptor does not preserve clavicles, but it does appear to preserve clavicle anchor pads. Can’t be sure. Just a guess for now.

Maybe the clavicles left markers of their departure.
If so one of those markers remains on the coracoid, another on the scapula. Or not. Just a guess at this point, if real. So this was a search with essentially no substantial results. Sometimes that happens.

References
Sereno PC, Forster CA, Rogers RR and Moneta AM 1993. Primitive dinosaur skeleton form Argentina and the early evolution of the Dinosauria. Nature 361, 64-66.
Sereno PC, Martínez RN and Alcober OA 2013. Osteology of Eoraptor lunensis (Dinosauria, Sauropodomorpha). Basal sauropodomorphs and the vertebrate fossil record of the Ischigualasto Formation (Late Triassic: Carnian-Norian) of Argentina. Journal of Vertebrate Paleontology Memoir 12: 83-179 DOI:10.1080/02724634.2013.820113
Yates AM and Vasconcelos CC 2005. Furcula-like clavicles in the prosauropod dinosaur MassospondylusJournal of Vertebrate Paleontology. 25 (2): 466–468. doi:10.1671/0272-4634(2005)025[0466:FCITPD]2.0.CO;2

wiki/Eoraptor

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