In many places in the South during the slavery period slaves were forbidden by law to learn to read and write. Literacy among slaves was feared by whites, and brought severe punishments.
So when former slaves were first counted in the 1870 Census, most could not spell their own names. The census takers were free to choose whatever spellings they wanted based on what they thought they heard. And they heard some pretty strange sounding names.
They heard names like "Jensie", "Buh", "Burnies" (male) and "Exer". The census counters simply spelled such names as best they could. So a name like Eliza in the 1870 Census may appear as Liza in 1880 and Litha in 1900. And Eucala may be spelled "Kayler", "Kayla" or "Euclar".
So the researcher of African American heritage can't get too hung up on spellings. Look for phonetic spellings and groups of names that you find appearing together throughout your research. Remember, all you want to do is identify people.