A few sauropods have bifurcated cervical ribs. The most dramatic example that I know of is the turiasaur Moabosaurus (Britt et al. 2017). Mike and I got to see that material on the Sauropocalypse back in 2016, which is how we got the photo above.

Western University of Health Sciences

Matt Wedel

::: {#attachment_21111 .wp-caption .aligncenter shortcode="caption" style="width: 1034px"}
[![](https://svpow.files.wordpress.com/2023/08/moabosaurus-byu-14063-labeled.jpg?w=480){.wp-image-21111
.size-large aria-describedby="caption-attachment-21111" loading="lazy"
attachment-id="21111"
permalink="http://svpow.com/2023/08/13/how-many-animals-have-bifurcated-cervical-ribs/moabosaurus-byu-14063-labeled/"
orig-file="https://svpow.files.wordpress.com/2023/08/moabosaurus-byu-14063-labeled.jpg"
orig-size="4000,2600" comments-opened="1"
image-meta="{\"aperture\":\"0\",\"credit\":\"\",\"camera\":\"\",\"caption\":\"\",\"created_timestamp\":\"0\",\"copyright\":\"\",\"focal_length\":\"0\",\"iso\":\"0\",\"shutter_speed\":\"0\",\"title\":\"\",\"orientation\":\"0\"}"
image-title="Moabosaurus BYU 14063 labeled" image-description=""
image-caption=""
medium-file="https://svpow.files.wordpress.com/2023/08/moabosaurus-byu-14063-labeled.jpg?w=300"
large-file="https://svpow.files.wordpress.com/2023/08/moabosaurus-byu-14063-labeled.jpg?w=1024"
width="480" height="312"
srcset="https://svpow.files.wordpress.com/2023/08/moabosaurus-byu-14063-labeled.jpg?w=480 480w, https://svpow.files.wordpress.com/2023/08/moabosaurus-byu-14063-labeled.jpg?w=960 960w, https://svpow.files.wordpress.com/2023/08/moabosaurus-byu-14063-labeled.jpg?w=150 150w, https://svpow.files.wordpress.com/2023/08/moabosaurus-byu-14063-labeled.jpg?w=300 300w, https://svpow.files.wordpress.com/2023/08/moabosaurus-byu-14063-labeled.jpg?w=768 768w"
sizes="(max-width: 480px) 100vw, 480px"}](https://svpow.files.wordpress.com/2023/08/moabosaurus-byu-14063-labeled.jpg)

BYU 14063, a left cervical rib of the turiasaur *Moabosaurus* in medial
view.
:::

A few sauropods have bifurcated cervical ribs. The most dramatic example
that I know of is the turiasaur *Moabosaurus* (Britt et al. 2017). Mike
and I got to see that material on the Sauropocalypse back in 2016, which
is how we got the photo above. Royo-Torres et al. (2006) had previously
described and figured bifurcated cervical ribs in *Turiasaurus*, but
they seem to be absent in *Mierasaurus* (Royo-Torres et al. 2017), which
is the sister taxon to *Moabosaurus*.

::: {#attachment_21114 .wp-caption .aligncenter shortcode="caption" style="width: 436px"}
[![](https://svpow.files.wordpress.com/2023/08/dicraeosaurus-cervical-ribs-janensch-1929-figs-21-23.jpg){.wp-image-21114
.size-full aria-describedby="caption-attachment-21114" loading="lazy"
attachment-id="21114"
permalink="http://svpow.com/2023/08/13/how-many-animals-have-bifurcated-cervical-ribs/dicraeosaurus-cervical-ribs-janensch-1929-figs-21-23/"
orig-file="https://svpow.files.wordpress.com/2023/08/dicraeosaurus-cervical-ribs-janensch-1929-figs-21-23.jpg"
orig-size="426,583" comments-opened="1"
image-meta="{\"aperture\":\"0\",\"credit\":\"\",\"camera\":\"\",\"caption\":\"\",\"created_timestamp\":\"0\",\"copyright\":\"\",\"focal_length\":\"0\",\"iso\":\"0\",\"shutter_speed\":\"0\",\"title\":\"\",\"orientation\":\"0\"}"
image-title="Dicraeosaurus cervical ribs – Janensch 1929 figs 21-23"
image-description="" image-caption=""
medium-file="https://svpow.files.wordpress.com/2023/08/dicraeosaurus-cervical-ribs-janensch-1929-figs-21-23.jpg?w=219"
large-file="https://svpow.files.wordpress.com/2023/08/dicraeosaurus-cervical-ribs-janensch-1929-figs-21-23.jpg?w=426"
width="426" height="583"
srcset="https://svpow.files.wordpress.com/2023/08/dicraeosaurus-cervical-ribs-janensch-1929-figs-21-23.jpg 426w, https://svpow.files.wordpress.com/2023/08/dicraeosaurus-cervical-ribs-janensch-1929-figs-21-23.jpg?w=110&h=150 110w, https://svpow.files.wordpress.com/2023/08/dicraeosaurus-cervical-ribs-janensch-1929-figs-21-23.jpg?w=219&h=300 219w"
sizes="(max-width: 426px) 100vw, 426px"}](https://svpow.files.wordpress.com/2023/08/dicraeosaurus-cervical-ribs-janensch-1929-figs-21-23.jpg)

Cervical ribs of *Dicraeosaurus* from Janensch (1929). Note the
dorsally-projecting bump on the shaft of the rib at the top.
:::

Tschopp et al. (2015: character 217, p. 99--100, fig. 49) recognized a
"posteriorly projecting spur on dorsolateral edge of \[the\] posterior
shaft" of the cervical rib in *Dicraeosaurus* and some apatosaurines.
That's not a complete bifurcation, but it's not a million miles out ---
at least, it's implying that a second muscle was pulling on the cervical
rib from a different direction as the first.

Sereno et al. (1999) reported that cervical ribs 3-6 of *Jobaria* have
an "accessory anterior process". This might mean that some of the
anterior processes of the cervical ribs are bifurcated in *Jobaria*, but
the character state is not illustrated and we have not been able to
observe the relevant fossils firsthand.

::: {#attachment_21117 .wp-caption .aligncenter shortcode="caption" style="width: 1034px"}
[![](https://svpow.files.wordpress.com/2023/08/zhuchengceratops-cervical-ribs-xu-et-al-2010-fig7.png?w=480){.wp-image-21117
.size-large aria-describedby="caption-attachment-21117" loading="lazy"
attachment-id="21117"
permalink="http://svpow.com/2023/08/13/how-many-animals-have-bifurcated-cervical-ribs/zhuchengceratops-cervical-ribs-xu-et-al-2010-fig7/"
orig-file="https://svpow.files.wordpress.com/2023/08/zhuchengceratops-cervical-ribs-xu-et-al-2010-fig7.png"
orig-size="1340,663" comments-opened="1"
image-meta="{\"aperture\":\"0\",\"credit\":\"\",\"camera\":\"\",\"caption\":\"\",\"created_timestamp\":\"0\",\"copyright\":\"\",\"focal_length\":\"0\",\"iso\":\"0\",\"shutter_speed\":\"0\",\"title\":\"\",\"orientation\":\"0\"}"
image-title="Zhuchengceratops cervical ribs – Xu et al 2010 fig7"
image-description="" image-caption=""
medium-file="https://svpow.files.wordpress.com/2023/08/zhuchengceratops-cervical-ribs-xu-et-al-2010-fig7.png?w=300"
large-file="https://svpow.files.wordpress.com/2023/08/zhuchengceratops-cervical-ribs-xu-et-al-2010-fig7.png?w=1024"
width="480" height="237"
srcset="https://svpow.files.wordpress.com/2023/08/zhuchengceratops-cervical-ribs-xu-et-al-2010-fig7.png?w=480 480w, https://svpow.files.wordpress.com/2023/08/zhuchengceratops-cervical-ribs-xu-et-al-2010-fig7.png?w=958 958w, https://svpow.files.wordpress.com/2023/08/zhuchengceratops-cervical-ribs-xu-et-al-2010-fig7.png?w=150 150w, https://svpow.files.wordpress.com/2023/08/zhuchengceratops-cervical-ribs-xu-et-al-2010-fig7.png?w=300 300w, https://svpow.files.wordpress.com/2023/08/zhuchengceratops-cervical-ribs-xu-et-al-2010-fig7.png?w=768 768w"
sizes="(max-width: 480px) 100vw, 480px"}](https://svpow.files.wordpress.com/2023/08/zhuchengceratops-cervical-ribs-xu-et-al-2010-fig7.png)

Cervical ribs of *Zhuchengceratops* from Xu et al. (2010: fig. 7). Fifth
cervical rib in lateral (I) and medial (J) views; sixth cervical rib in
medial (K) and lateral (L) views.
:::

Xu et al. (2010) described bifurcated cervical ribs in the
leptoceratopsid ceratopsian *Zhuchengceratops*, including in their
diagnosis "middle cervical ribs bifurcated due to presence of prominent
accessory dorsal process (condition poorly known in other
ceratopsians)". The cervical ribs of *Zhuchengceratops* show a whole
morphological spectrum, from an accessory dorsal process present as a
tiny bump, as in *Dicraeosaurus*, all the way to full bifurcation. Xu et
al. (2010) implied that this feature is also present in other
ceratopsians including *Triceratops*.

So...who else? Any non-avian theropods? Weird Triassic hellasaurs?
Attention-seeking salamanders? Cervical-rib-obsessed minds want to know.

## References

- Britt, Brooks B., Rodney D. Scheetz, Michael F. Whiting and D. Ray
  Wilhite. 2017. *Moabosaurus utahensis*, n. gen., n. sp., a new
  sauropod from the Early Cretaceous (Aptian) of North America.
  Contributions from the Museum of Paleontology, University of Michigan
  32(11):189--243.
- Janensch, Werner. 1929. Die Wirbelsäule der Gattung *Dicraeosaurus*.
  Palaeontographica, Supplement 7, 2:39--133 and plates I--VII.
- Royo-Torres, Rafael, Alberto Cobos and Luis Alcalá. 2006. A giant
  European dinosaur and a new sauropod clade. Science 314:1925--1927.
- Royo-Torres, Rafael, Paul Upchurch, James I. Kirkland, Donald D.
  DeBlieux, John R. Foster, Alberto Cobos and Luis Alcalá. 2017.
  Descendants of the Jurassic turiasaurs from Iberia found refuge in the
  Early Cretaceous of western USA. Scientific Reports 7:14311.
  doi:10.1038/s41598-017-14677-2
- Sereno, Paul C., Allison L. Beck, Didier. B. Dutheil, Hans C. E.
  Larsson, Gabrielle. H. Lyon, Bourahima Moussa, Rudyard W. Sadleir,
  Christian A. Sidor, David J. Varricchio, Gregory P. Wilson and
  Jeffrey A. Wilson. 1999. Cretaceous sauropods from the Sahara and the
  uneven rate of skeletal evolution among dinosaurs. Science
  282:1342--1347.
- Xu X, Wang K, Zhao X, Sullivan C, Chen S. 2010. A new leptoceratopsid
  (Ornithischia: Ceratopsia) from the Upper Cretaceous of Shandong,
  China and its implications for neoceratopsian evolution. PLoS ONE
  5(11): e13835.
  [https://doi.org/10.1371/journal.pone.0013835](https://doi.org/10.1371/journal.pone.0013835){rel="nofollow"}

 

------------------------------------------------------------------------

[doi:10.59350/rd3xz-bp274](https://doi.org/10.59350/rd3xz-bp274)


A New Leptoceratopsid (Ornithischia: Ceratopsia) from the Upper Cretaceous of Shandong, China and Its Implications for Neoceratopsian Evolution

{.wp-image-21111 .size-large aria-describedby=“caption-attachment-21111” loading=“lazy” attachment-id=“21111” permalink=“http://svpow.com/2023/08/13/how-many-animals-have-bifurcated-cervical-ribs/moabosaurus-byu-14063-labeled/” orig-file=“https://svpow.files.wordpress.com/2023/08/moabosaurus-byu-14063-labeled.jpg” orig-size=“4000,2600” comments-opened=“1”

Rogue Scholar Posts

How many animals have bifurcated cervical ribs?