Profile image
Story Views

Now:
Last Hour:
Last 24 Hours:
Total:

Little red flags for a Saharastega reconstruction

Thursday, March 2, 2017 11:09
% of readers think this story is Fact. Add your two cents.

(Before It's News)

Saharastega moradiensis (Sidor et al., 2005; Late Permian; Fig. 1) is a large, flat-headed, temnospondyl basal tetrapod. According to the original reconstruction (Fig. 1) it is the only temnospondyl in the large reptile tree (LRT, NOW 362 taxa, not yet updated) in which the jugal has no posterior process and the quadratojugal contacts the postorbital. Those autapomorphies raised red flags that started the present investigation.

Figure 1. Saharastega fossil skull, tracing of fossil skull, freehand reconstruction, all by Sidor et al., followed by color tracing that finds nares at the dorsal rostrum, concave dorsal rostrum and posterior jugal separating the quadratojugal from the postorbital overlooked by Sidor et al. ” data-medium-file=”https://pterosaurheresies.files.wordpress.com/2017/03/saharastega-insitu1.gif?w=584&h=531?w=300″ data-large-file=”https://pterosaurheresies.files.wordpress.com/2017/03/saharastega-insitu1.gif?w=584&h=531?w=584″ class=”size-full wp-image-26277″ src=”https://pterosaurheresies.files.wordpress.com/2017/03/saharastega-insitu1.gif?w=584&h=531″ alt=”Figure 1. Saharastega fossil skull, tracing of fossil skull, freehand reconstruction, all by Sidor et al., followed by color tracing that finds nares at the dorsal rostrum, concave dorsal rostrum and posterior jugal separating the quadratojugal from the postorbital overlooked by Sidor et al.” width=”584″ height=”531″ />

Figure 1. Saharastega fossil skull, tracing of fossil skull, freehand reconstruction, all by Sidor et al., followed by color tracing that finds nares at the concave dorsal rostrum and posterior jugal separating the quadratojugal from the postorbital

Taking the Saharastega freehand reconstruction at face value
Saharastega was scored and it nested with the coeval Nigerpeton (Fig. 2) which has dorsal nares and anterior fang holes along with a concave rostral profile. These are traits not shared by Saharastega according to the freehand reconstruction (Fig. 1).

Going back to the fossil
and colorizing the bones of Saharastega reveals a skull more like that of Nigerpeton than the freehand reconstruction indicates. It looks like the anterior nares of Saharastega may be fang holes, as in Nigerpeton. Both share dorsal nares and a concave rostral profile, together with a jugal that separates the quadratojugal from the postorbital. Note the placement of the internal nares relative to the external nares in Nigerpeton (Fig. 2). That pattern is more or less shared by Saharastega (Fig. 1).

Figure 2. Nigerpeton nests with its contemporary, Saharastega (figure 1) and has dorsal nares and a concave rostrum. ” data-medium-file=”https://pterosaurheresies.files.wordpress.com/2017/03/nigerpeton588.gif?w=584&h=943?w=186″ data-large-file=”https://pterosaurheresies.files.wordpress.com/2017/03/nigerpeton588.gif?w=584&h=943?w=584″ class=”size-full wp-image-26273″ src=”https://pterosaurheresies.files.wordpress.com/2017/03/nigerpeton588.gif?w=584&h=943″ alt=”Figure 2. Nigerpeton nests with its contemporary, Saharastega (figure 1) and has dorsal nares and a concave rostrum.” width=”584″ height=”943″ />

Figure 2. Nigerpeton nests with its contemporary, Saharastega (figure 1) and has dorsal nares and a concave rostrum.

The two taxa, Nigerpeton and Saharastega,
are not congeneric, but they do appear to share more traits than the authors originally indicated. The crack across the rostrum in Saharastega somewhat obliterated the nares. Otherwise they would have not been overlooked.

References
Sidor CA, O’Keefe FR, Damiani R, Steyer JS, Smith RMH, Larsson HCE, Sereno PC, Ide O and Maga A 2005. Permian tetrapods from the Sahara show climate-controlled endemism in Pangaea. Nature. 434 (7035): 886–889. doi:10.1038/nature03393. PMID 15829962.
Damiani R, Sidor CA, Steyer JS. Smith RMH, Larsson HCE, Maga A and Ide O 2006. The vertebrate fauna of the Upper Permian of Niger. V. The primitive temnospondyl Saharastega moradiensis. Journal of Vertebrate Paleontology. 26 (3): 559–572. doi:
wiki/Saharastega



Source: https://pterosaurheresies.wordpress.com/2017/03/03/little-red-flags-for-a-saharastega-reconstruction/

Report abuse

Comments

Your Comments
Question   Razz  Sad   Evil  Exclaim  Smile  Redface  Biggrin  Surprised  Eek   Confused   Cool  LOL   Mad   Twisted  Rolleyes   Wink  Idea  Arrow  Neutral  Cry   Mr. Green

Top Stories
Recent Stories
 

Featured

 

Top Global

 

Top Alternative

Register

Newsletter

Email this story
Email this story

If you really want to ban this commenter, please write down the reason:

If you really want to disable all recommended stories, click on OK button. After that, you will be redirect to your options page.