Original description as Chromis diagramma:
- Günther, Albert C. L. G. 1894. "Descriptions of the reptiles and fishes collected by Mr. E. Coode-Hore on Lake Tanganyika". Proceedings of the Zoological Society of London. v. 1893 (n. 4): pp. 628-632 (crc00212)
Conservation: Simochromis diagramma is evaluated by the international union for the conservation of nature in the iucn red list of threatened species as (LC) least concern (2006).