Ixos

Ixos is a paraphyletic songbird genus in the bulbul family, Pycnonotidae. Some authorities have advocated a complete merger of the genus Ixos with Hypsipetes – and even the entire 'Hypsipetes group' of bulbuls, which also includes Hemixos, Iole and Tricholestes –, being the oldest genus name Ixos would apply to all of them, rather than Hypsipetes as is often believed. This re-classification seems hardly appropriate however, since Alophoixus and Setornis cannot be excluded from the 'Hypsipetes group', and an all-out merge would turn the resultant 'genus' Ixos into an ill-defined 'wastebin taxon'. The erroneous inclusion of I. virescens in Hypsipetes has caused the Nicobar bulbul to be listed under its invalid junior synonym H. nicobariensis rather than the valid names H. virescens or I. nicobariensis. There are four extant species in the genus Ixos: Formerly, some authorities also considered the following species (or subspecies) as species within the genus Ixos: