Somali dialects are divided into three main groups: Northern, Benaadir and Maay. Northern Somali (or Northern-Central Somali) forms the basis for Standard Somali. Benaadir (also known as Coastal Somali) is spoken on the Benadir coast from Cadaley to south of Marka, including Mogadishu, and in the immediate hinterland. The coastal dialects have additional phonemes which do not exist in Standard Somali.
The Digil and Mirifle clans (sometimes called Rahanweyn) live in the southern areas of Somalia. Recent research (Diriye Abdullahi, 2000) has shown that, although previously classified with Somali, their languages and dialects are incomprehensible to many Somali speakers. The most important language of the Digil and Mirifle is Maay. Other languages in this category are Jiido, Dabare, Garre, and Central Tunni. Of all these, Jiido is the most incomprehensible to Somali speakers. One important aspect in which the languages of the Digil and Mirifle differ from Somali is the lack of pharyngeal sounds. The retroflex /ɖ/ is also replaced by /r/ in some positions.