Original description as Haplochromis petronius:
- Greenwood, Peter Humphry. 1973. "A revision of the Haplochromis and related species (Pisces: Cichlidae) from Lake George, Uganda". Bulletin of the British Museum (Natural History) Zoology Series. Series 25 (5); pp 141-242 (crc00219)
Conservation: Thoracochromis petronius is evaluated by the international union for the conservation of nature in the iucn red list of threatened species as (VU) vulnerable (2006).