Mesembriornis

Mesembriornis Temporal range: Late Miocene-Early Pliocene (Montehermosan-Chapadmalalan) ~6.8–3.0 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Leg bones
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Cariamiformes
Family:	†Phorusrhacidae
Subfamily:	†Mesembriornithinae
Genus:	†Mesembriornis Moreno, 1889
Type species
Mesembriornis milneedwardsi Moreno, 1889
Species
M. milneedwardsi Moreno, 1889 M. incertus Rovereto, 1914
Synonyms
Hermosiornis Rovereto, 1914 Palaeociconia australis Moreno, 1889 Prophororhacos

Mesembriornis is a genus of intermediate-sized phorusrhacids that grew up to 1.5 metres (4.9 ft) in height. They represent a well-distinct lineage of terror birds, differing from the massive large groups and the smaller Psilopterinae. In general proportions, they most resembled the Patagornithinae which flourished somewhat earlier, mainly to the south of the range of Mesembriornis.^[1] Fossils of the terror bird have been found in Montehermosan deposits of the Monte Hermoso Formation, as well as the Andalgala Formation and Chapadmalal Formation in Argentina.^[2]