Haplochromis squamipinnis Regan, 1921 Figs 1–2, 38–40; Table 1 Haplochromis squamipinnis Regan, 1921: 636. Haplochromis squamipinnis – Trewavas 1933: 338 (redescription). — Greenwood 1973: 204, fig. 31 (redescription). Harpagochromis squamipinnis – Greenwood 1980: 13. Differential diagnosis Species with a piscivorous morphology; body rather deep [BD 32.4–39.3 (mean 35.7) % SL]; oral jaws very long [LJL 47.8–58.6 (52.7) % HL], narrow [LJW 32.6–44.7 (37.2) % LJL], and steep (gape inclination 30–45°); outer oral teeth many and small [UOT 39–79 (median 58)]; dominant males slate blue. Amongst piscivorous species from the Lake Edward system, H. squamipinnis differs from all by presence vs absence of minute scales on proximal part of dorsal fin (rarely few scales present in H. quasimodo sp. nov.). It further differs from H. latifrons sp. nov. and H. mentatus by the combination of small vs large outer oral teeth, a larger number of outer upper jaw teeth [UOT 39–79 (58) vs 22–47 (27–36)], a steeper gape (30–45° vs 15–30°), and a deeper body [BD 32.4–39.3 (35.7) vs 27.2–32.3 (28.6–31.2) % SL]; from H. mentatus by dominant males uniformly slate blue vs yellow-green with a red anterior part of flank. It further differs from H. rex sp. nov., H. simba sp. nov., H. glaucus sp. nov., and H. aquila sp. nov. by the combination of small vs large outer oral teeth, a larger number of outer upper jaw teeth [UOT 39–79 (58) vs 22–47 (27–36)], and dominant males uniformly slate blue vs cream-coloured with an orange operculum, yellow with an orange anterior part of flank, light blue with a dusky to black head, or light grey with a black head, respectively; further from H. rex sp. nov., H. simba sp. nov., and H. glaucus sp. nov. by a steeper gape (30–45° vs 15–30°); further from H. aquila sp. nov. by a smaller eye [ED 23.1–29.7 (26.6) vs 30.0–31.5 (30.6) % HL]. It further differs from H. kimondo sp. nov. by a concave to straight vs convex dorsal outline of head, a gentler snout inclination (30–40° vs 40–50°), and dominant males slate blue vs grey dorsally and yellow ventrally; further from H. falcatus sp. nov. by a shorter head [HL 35.1–36.9 (36.0) vs 36.6– 39.6 (38.2) % SL] and dominant males slate blue vs olive-green with an orange-red anterior part of flank; further from H. curvidens sp. nov. and H. pardus sp. nov. by a deeper cheek [ChD 24.9–36.0 (29.0) vs 20.8–24.9 (22.5–23.2) % HL]; further from H. pardus sp. nov. by a larger adult size (max. 211 vs 96 mm SL) and colour pattern of small specimens ( 120 mm SL), tri- to rarely unicuspid in upper jaw and uni- to weakly tricuspid in lower jaw of small specimens ( 210 mm SL.

Published as part of Vranken, Nathan, Steenberge, Maarten Van, Heylen, Annelies, Decru, Eva & Snoeks, Jos, 2022, From a pair to a dozen: the piscivorous species of Haplochromis (Cichlidae) from the Lake Edward system, pp. 1-94 in European Journal of Taxonomy 815 on pages 68-73, DOI: 10.5852/ejt.2022.815.1749, http://zenodo.org/record/6484153