Alibamu

From Alabama River by early European explorers and named "Alibamu" after the local Indian tribe

infoplease - Daily Almanac 2008

From my readings, Koasati is closest to Alibamu, then Appalachee, and then Mikasuki.

languagehat.com: MUSKOGEAN AND LAMB'S-QUARTERS. 2005

The Koasati seem to have included the ancient Alibamu of central Alabama, while the Hitchiti, on lower Chattahoochee river, appear to have been the remnant of the ancient people of southeast Georgia, and claimed to be of more ancient occupancy than the Muscogee.

languagehat.com: MUSKOGEAN AND LAMB'S-QUARTERS. 2005

_ -- There is an Alibamu town on Deep Creek, Indian Territory, an affluent of the Canadian, Indian Territory.

Seventh Annual Report of the Bureau of Ethnology to the Secretary of the Smithsonian Institution, 1885-1886, Government Printing Office, Washington, 1891 John Wesley Powell 1868

There are Alibamu about 20 miles south of Alexandria,

Seventh Annual Report of the Bureau of Ethnology to the Secretary of the Smithsonian Institution, 1885-1886, Government Printing Office, Washington, 1891 John Wesley Powell 1868

So far as known only three women of the Apalachi survived in 1886, and they lived at the Alibamu town above referred to.

Seventh Annual Report of the Bureau of Ethnology to the Secretary of the Smithsonian Institution, 1885-1886, Government Printing Office, Washington, 1891 John Wesley Powell 1868