Excerpt from change request document:

The Musi river is the longest in Sumatra, and many speech varieties are spoken along its length. Musi and the other Malay varieties listed in 4a were listed in the 1981 Wurm and Hattori linguistic atlas as being Malay dialects, but were incorrectly interpreted in previous Ethnologue editions as distinct languages. Language surveys completed in 2006-2007 found comprehension between these Malay dialects, and a set of shared phonological innovations. The above "languages" should be listed as dialects of Musi.

MUSI--language (internal structure) Musi group Palembang group

Musi, Rawas, Pegagan Palembang, Lowland Malay

It was found that there was high reported comprehension between the speech varieties found along the coastal plain of South Sumatra and those centered around the city of Palembang, making a Palembang subgroup. The speech varieties of Downstream Lematang, Belide, and Penesak also had a high rate of reported comprehension, and form a Lowland Malay subgroup. The Palembang and the Lowland Malay subdialects together form the Palembang Malay subgroup of the Musi language. The other subgroup in the Musi language is the Musi subgroup, which is comprised of the Musi, Pegagan, and Rawas dialects. The Musi and Pegagan speech varieties share phonological innovations. Rawas has one of the phonological innovations, as well as some of its own. There is high reported comprehension between the Musi and Rawas and a high percentage of shared lexical items. The culture, phonological innovations, and reported comprehension in the Musi river basin dialect chain provide a reasonable basis for grouping these dialects of Malay (as ) as a distinct language. Moreover, the cultural and linguistic differences, distinct phonological innovations, along with lower reported comprehension between isolects of the Musi language and those of Central Malay (Pasemah, Semendo, Enim, etc.) argue against subsuming them all under "South Sumatran Malay".