Siouan languages
Authors who call the entire family "Siouan" distinguish the two branches as "Western Siouan" and "Eastern Siouan" or as "Siouan-proper" and "Catawban". Others restrict the name "Siouan" to the western branch and use the name "Siouan–Catawban" for the entire family. Generally, however, the name "Siouan" is used without distinction.
Siwai language
Motuna or Siwai, also known as "Telei, Rugara", is a Papuan language of Bougainville Province, Papua New Guinea. The current number of speakers is difficult to estimate since the latest figure (6,000 + 600) is from the 1970 census.