| Pectodens Temporal range: Anisian,
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| Holotype fossil | |
Scientific classification 
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| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Clade: | Archosauromorpha |
| Family: | †Trachelosauridae |
| Genus: | †Pectodens Li et al., 2017 |
| Type species | |
| Pectodens zhenyuensis Li et al., 2017
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Pectodens (meaning "comb tooth") is an extinct genus of archosauromorph reptile which lived during the Middle Triassic in China. The type and only species of the genus is P. zhenyuensis, named by Chun Li and colleagues in 2017. It was a member of the Archosauromorpha, specifically part of the unnatural grouping Protorosauria. However, an unusual combination of traits similar (such as the long neck) and dissimilar (such as the absence of a hook on the fifth metatarsal bone) to other protorosaurs initially led to confusion over its evolutionary relationships. In 2021, it was placed in a newly-established group, Dinocephalosauridae, along with its closest relative Dinocephalosaurus.
A small, slender animal measuring 38 centimetres (15 in) long, Pectodens was named after the peculiar comb-like arrangement of long, conical teeth present in its mouth. Unlike Dinocephalosaurus and the other reptiles that it was preserved with, well-developed joints and claw-like digits indicate that Pectodens was entirely terrestrial. However, its presence in marine deposits suggests that lived relatively close to the coastline. Its skeleton was also poorly ossified, which is typically a trait of aquatic animals, but this may have been due to the young age of the only known specimen instead.