We study the rank-frequency distribution of syllables in texts from written press in Bamana and Guinean Maninka, two closely related languages from the Manding group of the Mande family in West Africa. Five issues of widely circulating newspapers are analyzed in each language. The Bamana texts are written in a Roman-based alphabet without marking of tones, while Maninka texts are published in the N'ko alphabet comprising a superficial notation of tones. For the sake of comparisons , the Maninka data are also compiled for syllables with tonal distinctions neglected. The obtained rank-frequency distributions of syllables are fitted using two discrete distributions, Jain-Poisson and positive negative binomial, as well as the continuous Yule distribution. In most cases, a satisfactory fit was achieved, with the determination coefficient R 2 > 0.95 and discrepancy coefficient C < 0.02. The relation of the Yule distribution and Zipf's law with respect to the number of syllable types is discussed.