and a group that includes Plesiopithecus and crown lemuriforms. However, if azibiids are simians, as originally suggested with Algeripithecus, then they demonstrate an ancient simian lineage and their evolutionary divergence on the continent of Africa, contrary to the competing view that simians first evolved in Asia. Taxonomy The first species, Azibius trerki, was originally described by Jean Sudre in 1975 as a possible 'paromomyiform' (a type of plesiadapiform, an extinct group of arboreal mammals considered to be a sister group to the primate clade), but was also interpreted as a hyopsodontid (a type of extinct condylarth) by paleoanthropologist Frederick S. Szalay that same year. The following year, paleoanthropologist Philip D. Gingerich reclassified it as an adapid (an extinct type of adapiform primate from Europe). Throughout the 1990s and 2000s, debates over its classification continued, with some researchers suggesting it might be related to macroscelidids (elephant shrews), while others supported initial interpretations as adapids or plesiadapiforms (particularly carpolestids). In 2006, paleoanthropologist Marc Godinot favored a relationship between Azibius and simians, but tentatively suggested Azibius may be more closely related to toothcombed primates, which include all extant strepsirrhines. This latter view has gained increasing support with the reclassification of Algeripithecus (once considered a basal simian) as a closely related azibiid. Additional fossil teeth and the maxilla (upper jaw) of both genera discovered between 2003 and 2009 helped demonstrate their relationship. Based on the same fossil finds, Tabelia—which was also considered to be one of the oldest known simians along with Algeripithecus—is also now considered to be a synonym of Azibius. Also, the third and fourth lower premolars (P3 and P4) distinguish azibiids from carpolestids, while the upper fourth premolar (P4) matches what was thought to be the second upper molar (M2) of Dralestes hammadaensis, another suspected plesiadapiform or genus of azibiid. Specimens of Dralestes are now recognized as being either Azibius and Algeripithecus, and Tabuce et al. claimed that Dralestes was a synonym of Azibius in 2009. However, in 2010, Godinot cautiously suggested that Dralestes may be a synonym of Algeripithecus based on a blade-like premolar. He also reasserted his view that Algeripithecus was a simian based on its upper molar morphology and hypothesized that this applied to all azibiids, favoring his earlier view that they may be early simians instead of stem lemuriforms. The argument for strepsirrhine affinities was strengthened in 2011 when Marivaux et al. published an interpretation of recently