Several languages have been claimed to have such sounds, such as Margi and Bura in Nigeria. However, most researchers interpret them as having sequences of labial and coronal consonants, a rather common occurrence in Africa. The Yélî Dnye language of Rossel Island, Papua New Guinea, appears to be unique in having distinct labial–alveolar and labial–postalveolar places of articulation, as illustrated below. (The alveolars are fronted, and the post-alveolars only slightly retracted, so it may be best not to consider the latter to be retroflex as they are sometimes described.)
