Greeting the neighbor

A primitive amphibian in the Carboniferous period in the North of Chile, he meets a neighbor of the area, who is not very happy to see him, showing his teeth in a threatening position.
https://www.palass.org/publications/palaeontology-journal/archive/29/3/article_pp519-526
https://www.mnhn.gob.cl/613/w3-article-55022.html?_noredirect=1
https://www.latercera.com/que-pasa/noticia/exitosa-primera-expedicion-paleontologica-a-la-precordillera-de-atacama-descubre-fosiles-de-320-millones-de-anos/MSAQE5IK2FB7HNY47IFYURTRCI/