The stem catarrhine Saadanius does not inform the timing of the origin of crown catarrhines

A precise knowledge of the divergence time between Hominoidea (apes and humans) and Cercopithecoidea (Old World monkeys) has been hampered by the paucity of fossils between the early Miocene (23 Ma) and the early Oligocene (30 Ma). The earliest known Old World monkey is represented by Victoriapithecus macinnesi from Kenya, dated to 19 Ma (Benefit and McCrossin, 2002, Pilbeam and Walker, 1968), while several potential early hominoid fossils are dated to around 20 Ma, including Proconsul at 20–22.5 Ma (Harrison, 2010, Harrison and Andrews, 2009), Morotopithecus at 20 Ma (Gebo et al., 1997), and Ugandapithecus at 19–20 Ma (Senut et al., 2000). Kamoyapithecus, only known from some isolated dentition, dates back to the late Oligocene (23.9–27.8 Ma); however, its phylogenetic position remains controversial and not all authors classify it as a crown catarrhine (Harrison, 2002, Leakey et al., 1995). Based on this evidence in the fossil record, the divergence between hominoids and cercopithecoids is understood to be older than 20 Mya and most molecular estimates of primate divergences have used this as a calibration point (Chatterjee et al., 2009, Fabre et al., 2009, Hodgson et al., 2009, Raaum et al., 2005, Steiper and Young, 2008)