the Popo Agie Formation of the Chugwater Group of Wyoming. Synonymy of Koskinonodon with Anaschisma started when Romer (1947) proposed that Anaschisma was a senior synonym of Buettneria, Koskinonodon, and Borborophagus. This was followed by Gee et al. (2019), where they redescribed the holotypes of the two nominal Anaschisma species, and then synonymized Koskinonodon, Buettneria and Borborophagus with Anaschisma. The species B. bakeri which has long been assigned to the various synonyms of Anaschisma, was moved to its own genus, Buettnererpeton, in 2022. Description The skull of Anaschisma differs from the skulls of other closely related organisms in a few key ways. It is wider overall and features eye sockets that are very anterior and forward oriented, more so than its contemporaries. Also, the skull has prominent slime canals, which are used for transporting mucus, as well as large external nares. In addition, the upper jaw is relatively weak and thin, used only for holding teeth. Their large jaws could have held many teeth at once, maybe even over 100 on each side of the upper and lower jaws, but the actual number varies constantly over the animal's lifetime due to natural causes such as fighting, eating, disease, etc. The sheer size of the skull is one of the most defining traits for the genus Anaschisma. Other more minor skull traits characterize Anaschisma as well: elongation of the lachrymal, shortening of the prefrontal, reduction of the interclavicle, and the most characteristic is the center lachrymal entering margin of the orbit. While the shortened prefrontal is a characteristic of the family Metoposauridae, it is shorted even more in Anaschisma. The interclavicle is reduced in the way that it has many hexagonal pits as well as grooves and ridges. The skull of Anaschisma is also covered in this reticulate ornamentation. Some researchers believe that Anaschisma has a shorter posterior process of the interclavicle, which may discriminate it from other closely related species, while others believe that there is not enough information to make that distinction. Anaschisma also has ossified opisthotics, the more posterior of the bones surrounding the inner ear. Anaschisma had sharp, pointy teeth for catching and killing prey. They had marginal teeth as well as larger teeth on the palate, specifically palatine and ectopterygoid teeth. They had two basic types: large with shallow grooves and small with deeper grooves. These grooves run lengthwise down the teeth and aided the animals