| Arsinoitheriidae Temporal range:  | |
|---|---|
|   | |
| Skeleton of Arsinoitherium zitteli | |
| Scientific classification   | |
| Kingdom: | Animalia | 
| Phylum: | Chordata | 
| Class: | Mammalia | 
| Order: | † Embrithopoda | 
| Family: | † Arsinoitheriidae Andrews, 1904 | 
| Genera | |
Arsinoitheriidae is a family of mammals belonging to the extinct order Embrithopoda. [1] Remains have been found in the Middle East, Africa, Asia and Romania. Arsinotheriids were closely related to hyraxes, elephants, sirenians, and possibly desmostylians (as part of the superorder Afrotheria). [2] The name of the clade honors the wife of Ptolemy II, Queen Arsinoe II of Egypt, as the first fossils of Arsinoitherium were found near the ruins of her palace. [3]
 
 Arsinoitheriids are easily recognized by their prominent nose horns, which, in life, were likely covered in keratin. [4] The horns are derived from the nasal bones. [5] They are also characterized by pseudolophodont molars. [6] They also had small incisors, which may have asked as some form of tusk. [3]
Based on the less derived traits of Namatherium , it is assumed that Arsinoitheriidae underwent a divergent evolution sometime during the Lutetian. [7] The latest living genus, Arsinoitherium , was first recovered from the Latest Eocene of the Fayum [8] ; it disappears from the fossil record altogether before the end of the Early Oligocene. [8]