Cai-Long
Cai-Long-Waxiang
Waxiang
Cai-Long
Caijia
Longjia
Luren
Layers:
Burmo-Qiangic independent branch
Old Southwestern Chinese
Southwestern Mandarin
Homeland: Wu River watershed
Note that I have decided to name the branch containing Caijia, Longjia, and Luren as Cai-Long (-jia simply means 'home' or 'clan.'). Cai-Long-Waxiang would refer to Caijia, Longjia, Luren, and Waxiang grouped together.
Caijia, Longjia, and Luren of western Guizhou have no immediately recognizable close relatives, but Bai has been suggested as a close relative (Zhengzhang 2010). Waxiang Chinese is related according to Sagart (2011). However, while the superstrata of Bai and the Cai-Long languages belong to similar forms of western Old Chinese dialects, the substrata languages of Bai and Cai-Long constitute separate, independent southern branches of Burmo-Qiangic. The superstratum of Bai and Cai-Long was the first to split off from Old Chinese, even before Min (following Sagart 2011 on Caijia-Waxiang as the first branch to split from Old Chinese).
Cai-Long languages and Bai both have Burmo-Qiangic substrata, but the substrata of each of these two branches would have belonged to different branches of Burmo-Qiangic. Hence, the superficial similarities between Bai and the Cai-Long-Waxiang are due to (1) shared features due to the same Old Southwestern Chinese superstratum that is common to Bai, Cai-Long, and Waxiang, and (2) shared retentions from Proto-Burmo-Qiangic in the substratum layer. Thus, pre-Bai and pre-Cai-Long-Waxiang were each separate branches of Burmo-Qiangic. Pre-Cai-Long-Waxiang would have had a much wider geographical distribution in the past, and would have been spread across much of northern Guizhou. The distribution of Cai-Long languages at the southwestern end of the Wu River watershed and Waxiang Chinese at the eastern end of the Wu River watershed suggests that Proto-Cai-Long-Waxiang had spread upstream along the course of the Wu River from the Sichuan Basin, undergoing influence from Old Southwestern Chinese along the way. Old Southwestern Chinese would have likely been centered in the Sichuan Basin, spreading in a star-like manner from the circularly-shaped Sichuan Basin.
List of reconstructions (preliminary)
Proto-Cai-Long forms of Old Chinese origin
(Old Chinese [OC] and Middle Chinese [MC] forms are from Baxter & Sagart (2014)).
Proto-Cai-Long forms of non-Sinitic origin
(Old Chinese [OC] and Middle Chinese [MC] forms are from Baxter & Sagart (2014)).
Possible loanwords
Possible loanwords from Austroasiatic include the words for 'excrement' and 'pig.'
Sources
Bo Wenze [薄文泽]. 2004. "A sketch of Caijia [蔡家话概况]". In Minzu Yuwen.
Caiguan Town Gazetteer [蔡官镇志] (2004). Guiyang: Guizhou People's Press [贵州人民出版社].
Guizhou provincial ethnic classification commission, linguistic division [贵州省民族识别工作队语言组]. 1982. The language of the Caijia [Caijia de yuyan 蔡家的语言]. m.s. [Unpublished government draft manuscript]
Guizhou provincial ethnic classification commission [贵州省民族识别工作队]. 1984. Report on ethnic classification issues of the Nanlong people (Nanjing-Longjia) [南龙人（南京-龙家）族别问题调查报告]. m.s. [Unpublished government draft manuscript]
Guizhou Province Gazetteer: Ethnic Gazetteer [贵州省志. 民族志] (2002). Guiyang: Guizhou Ethnic Publishing House [貴州民族出版社].
Liupanshui City Gazetteer: Ethnic Gazetteer [六盘水市志: 民族志] (2003). Guiyang: Guizhou People's Press [贵州人民出版社].
Wu Yunji, Shen Ruiqing [伍云姬、沈瑞清]. 2010. An Investigative Report of Waxianghua of Guzhang County, Xiangxi Prefecture [湘西古丈瓦乡话调查报告]. Shanghai Educational Press [上海教育出版社].
Yang Wei [杨蔚]. 1999. A study of Yuanling Waxianghua [沅陵乡话研究]. Changsha: Hunan Educational Press [湖南敎育出版社].
Wang Feng. 2006. Comparison of languages in contact: the distillation method and the case of Bai. Language and Linguistics Monograph Series B: Frontiers in Linguistics III. Taipei: Institute of Linguistics, Academia Sinica.