The Basaa languages are a clade of Bantu languages coded Zone A.40 in Guthrie's classification. According to Nurse & Philippson (2003), the languages remaining from the formation of the Mbam

Mbam languages

The Mbam languages are a group of erstwhile zone-A Bantu languages which some lexicostatistical studies suggest are not actually Bantu, but related Southern Bantoid languages. Janssens posited that they are all of Guthrie's zone A.60 languages, half of his A.40 languages, and perhaps Bube...

 group form a valid node. They are:

Basaa

Basaa language

Basaa is a Bantu language spoken in Cameroon. It is spoken by about 230,000 people in Centre and Littoral provinces.-Vowels:-Consonants:...

, Rombi

Rombi language

Lombi is a language spoken in the Meme department of the Southwest Province of southwestern Cameroon by the Barombi people. It has a lexical similarity of 86% with Bankon, which is spoken in the nearby Moungo department of Littoral Province.-References:**...

–Bankon

Bankon language

Bankon is a Bantu language spoken in the Moungo department of the Littoral Province of southwestern Cameroon. It has a lexical similarity of 86% with Rombi which is spoken in the nearby Meme department of Southwest Province....

, Kogo (Bakoko).

Hijuk was listed as unclassified A.50 in Guthrie, but according to Ethnologue it is quite similar to Basaa.