Saurodektes: Filling in the missing parts

Saurodektes rogersorum
is a small owenettid lepidosauromorph (BP/1/6025, Early Induan, Early Triassic) originally named “Saurodectes” by Modesto et al. (2003), but that name was preoccupied by a fossil louse. The holotype of Saurodektes is known from a partial skull and anteriormost postcrania (Fig. 1).

Figure 1. Saurodektes (originally Saurodectes) by Modesto et al. 2003 (black/white). Missing parts in color based on phylogenetic bracketing.

Figure 1. Saurodektes (originally Saurodectes) by Modesto et al. 2003 (black/white). Missing parts in color based on phylogenetic bracketing.

The missing parts of the skull
can be restored using phylogenetic bracketing after phylogenetic analysis. In the large reptile tree Saurodektes nests at the base of the Owenetta clade, between the Nyctiphruretus and Barasaurus clades.

Procolophonomorpha?
No. All of these taxa nest far from Procolophon and kin, which nest with Diadectes and kin.

Lepidosauriformes?
Almost. These taxa were ancestral to Paliguana and the Lepidosauriformes, which gave rise to all living lizards and a host of extinct relatives, including pterosaurs.

Nascent upper temporal fenestra?
No. While the tiny space between the parietal and large supratemporal appears to be creating an upper temporal fenestra in Saurodektes, in lepidosauriformes the supratemporal is reduced and migrates to the back as it it is replaced by the squamosal, which comes to rim the upper temporal fenestra. Best to consider those cranial holes as damaged goods here in Saurodektes.

References
Modesto SP, Damiani RJ, Neveling J,Yates AM 2003. A new Triassic owenettid parareptile and the Mother of Mass Extinctions. Journal of Vertebrate Paleontology 23 (3): 715.

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