Thou-Kathu language

Kathu and Thou () constitute a Lolo-Burmese language of Balong (坝聋), Nanping Township (南屏镇), Guangnan County, Yunnan, China. The Kathu are locally known as the White Yi (白彝). Wu Zili (2004) estimates that Kathu has a total of more than 7,000 speakers in Guangnan County (including in Dayashao 大牙少), as well as in Jinping County, Yunnan. "Ethnologue" mentions a possible presence in Guangxi Province.
Kathu-Thou is notable for having initial consonant clusters, which within the Lolo-Burmese branch are also found in Written Burmese (Old Burmese) and Jinuo (Hsiu 2014:66). Wu (2004) lists the onset clusters pl, pʰl, bl, ml, kl, kʰl, gl, ql, qʰl, ɢl, ŋl.
Varieties.
Hsiu (2014:65) identifies two varieties, both spoken in Nanping Township (南屏镇).
Classification.
Kathu vocabulary is largely similar to those of other Mondzish languages. However, there are various words that do not appear to be of Lolo-Burmese origin, and are derived from an unknown Tibeto-Burman branch (Hsiu 2014). Hsiu (2014) suggests that Kathu could be added to George van Driem's list of Trans-Himalayan "fallen leaves."
Bradley (1997) classified Kathu as a Northern Loloish language, while Bradley (2007) classified it as a Southeastern Loloish language. However, Pelkey (2011:458) notes that Kathu and Mo'ang are not Southeastern Loloish languages.