Cosung

Definitely endangered, around 47000 native speakers

The Loloish language Cosung (Khucong, Kucong) or Lahlu is spoken in Yunnan and Vietnam. The speakers' autonym in Vietnam is khu33 tsh33, and they are also known as the La H Na 'Black Lahu' (Edmondson 2002). It has a strong resemblance to Lahu.
According to Sun Hongkai (1992), 30,000 Kucong speakers live in Yunnan, China. Chang (2011:5) recognizes three Kucong branches.
Black Kucong (Lahu Na; autonym Guocuo or Guochou) is a Vietnamese language spoken in the counties of Zhenyuan, Mojiang, Jiangcheng, Yuanjiang, and Mengla, as well as the Mng Tè District. Chang Suanzhi (2011) discusses the Shaohuiqing[zhai] dialect of Shaohuiqing[zhai], Dangduo Village, Yangjie Township, Yuanjiang County. In Jinping County, Yellow Kucong (Lahu Shi) is spoken.
White Kucong (Lahu Pu) is spoken in two villages in Jinping County's Zhemi Township. 

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Sources:

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Kucong at Ethnologue. Retrieved 12 November 2021

Dai, Qingxia 戴庆厦; Chang, Junzhi 常俊之 (2009). "Yuánjiāng kǔcōnghuà gàikuàng" 元江苦聪话概况 [Yuanjiang Kucong Dialect Overview]. Minzu yuwen 民族語文 (in Chinese)

Li, Jie 李洁; Zhang, Wei 张伟 (2003). "Kǔcōnghuà gàikuàng" 苦聪话概况 [Kucong Dialect Overview]. Minzu yuwen 民族語文. 2003

 "Yuánjiāng xiàn mīlī xiāng gānchà cūnmín wěiyuánhuì mànshā > xiāngcūn gàikuàng" 元江县咪哩乡甘岔村民委员会漫沙 > 乡村概况 [Mansha, Gancha Village Committee, Mili Township, Yuanjiang County > Rural Area Overview]. ynszxc.gov.cn (in Chinese). Archived from the original