orthognathus, Petrochromis Matthes [H.] 1959:17 [Folia Scientifica Africae Centralis v. 5 (no. 1); ref. 34675] Lake Tanganyika. Holotype: MRAC 125150. Paratypes: MRAC 125151-55 (5), 125156-61 (6), 125162-64 (3), 125165-67 (3), 125168-71 (4), 125172-75 (4), 126185-94 (10), 126195-199 (5). Species illustrated and described in more detail in Matthes 1959:335 [ref. 12007]. •Valid as Petrochromis orthognathus Matthes 1959 -- (Maréchal & Poll 1991:371 [ref. 20946], Takahashi & Koblmüller 2014:262 [ref. 33264], Konings 2015:272 [ref. 34660], Konings 2019:287 [ref. 36983]). Current status: Valid as Petrochromis orthognathus Matthes 1959. Cichlidae: Pseudocrenilabrinae. Distribution: Eastern Africa: northern Lake Tanganyika. Habitat: freshwater.