Fedexia joins the LRT

Berman et al. 2010
brought us a new trematopid amphibian, Fedexia striegeli (Figs. 1-3; CM 76867; late Carboniferous; 300 mya; est. .6m long). Not quite matching the Berman et al. study, the large reptile tree (LRT, 1326 taxa) nests Fedexia at the base of the clade including Tambachia and Ecolsonia. This appear to be due to taxon exclusion

Figure 1. Fedexia skull in several views.

Figure 1. Fedexia skull in several views from Berman et al. 2018. 11.5 cm in length.

Firsthand observation
initially mistook the exposed teeth for a fern frond. The naris is elongated, covering a majority of the lateral rostrum. The orbit appears to be taller than wide, but when calipers are placed on it, the horizontal and vertical are identical. A small notch appears between the ventral premaxilla and maxilla. The lateral premaxillary teeth are enlarged to fangs.

Figure 1. Fedexia overall, from Berman et al., 2010.

Figure 2. Fedexia overall, from Berman et al., 2010.

Sister taxa
like Ecolsonia and Tambachia (Fig. 3) are similar in size and overall morphology.

Figure 3. Fedexia to scale alongside sisters Tambachia and Ecolsonia.

Figure 3. Fedexia to scale alongside sisters Tambachia and Ecolsonia. Note the large nares with a long lacrimal at the ventral margin, The quadratojugal may enclose all three taxa as it does in Ecolsonia.

Figure 4. Subset of the LRT focusing on amphibians including the frog, Rana. Fedexia nests here with Tambachia and Ecsolina.

Figure 4. Subset of the LRT focusing on amphibians including the frog, Rana and the salamander, Andrias. Fedexia nests here with Tambachia and Ecolsonia.

References
Berman DS, Henrici AC, Brezinski DK and Kollar AD 2010. A new trematopid amphibian (Temnospondyli: Dissorophoidea) from the Upper Pennsylvanian of western Pennsylvania: earliest record of terrestrial vertebrates responding to a warmer, drier climate PDF. Annals of Carnegie Museum. 78 (4): 289–318. doi:10.2992/007.078.0401

https://en.wikipedia.org/wiki/Fedexia

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