Type locality of the lectotype of Synodontis zanzibaricus: 'wahrscheinlich von Mombas' (Ref. 92837; lectotype by Ref. 82238). Known from the Pangani drainage (Ref. 52331), Galani-Sabaki River (Ref. 30558, 52331), lower Tana River (Ref. 39831, 52331, 78218) and Northern Ewaso Nyiro River (Ref. 52331). It inhabits the deep parts of the main river of the Galana-Sabaki draiange system (Ref. 30558). Also reported by Whitehead (1959) (=Ref. 41458) from the Tana River and Northern Ewaso Nyiro River as Synodontis zambezensis, a misidentification (Ref. 52331).