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. 2018 Nov 6:5:180244.
doi: 10.1038/sdata.2018.244.

X-ray computed microtomography of Megachirella wachtleri

Tiago R Simões  1 , Michael W Caldwell  1   2 , Mateusz Tałanda  3 , Massimo Bernardi  4   5 , Alessandro Palci  6   7 , Oksana Vernygora  1 , Federico Bernardini  8   9 , Lucia Mancini  10 , Randall L Nydam  11
Affiliations

X-ray computed microtomography of Megachirella wachtleri

Tiago R Simões et al. Sci Data. .

Abstract

Understanding the origin and early evolution of squamates has been a considerable challenge given the extremely scarce fossil record of early squamates and their poor degree of preservation. In order to overcome those limitations, we conducted high-resolution X-ray computed tomography (CT) studies on the fossil reptile Megachirella wachtleri (Middle Triassic, northern Italy), which revealed an important set of features indicating this is the oldest known fossil squamate in the world, predating the previous oldest record by ca. 75 million years. We also compiled a new phylogenetic data set comprising a large sample of diapsid reptiles (including morphological and molecular data) to investigate the phylogenetic relationships of early squamates and other reptile groups along with the divergence time of those lineages. The re-description of Megachirella and a new phylogenetic hypothesis of diapsid relationships are presented in a separate study. Here we present the data descriptors for the tomographic scans of Megachirella, which holds fundamental information to our understanding on the early evolution of one of the largest vertebrate groups on Earth today.

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Conflict of interest statement

The authors declare no competing interests.

Figures

Figure 1
Figure 1. Segmentation procedure of the CT scan data of Megachirella wachtleri.
(a) Sample slice of the whole-body scan of Megachirella. (b) Sample slice of the head-only scan of Megachirella. Each scan is composed of hundreds or thousands of slices that were subsequently used for individual segmentation procedures. (c) Whole skeleton after segmentation in dorsal view. (d) Whole skeleton after segmentation in ventral view. (e) Skull and mandibles after segmentation of individual components of the head in dorsal view. (f) Skull and mandibles after segmentation of individual components of the head in ventral view.
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References

Data Citations

    1. Simões T. R., et al. . 2018. figshare. https://doi.org/10.6084/m9.figshare.c.4157321 - DOI

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