Wallaceochromis, Lamboj, Trummer & Metscher, 2016

Lamboj, Anton, Trummer, Franziska & Metscher, Brian D., 2016, Wallaceochromis gen. nov, a new chromidotilapiine cichlid genus (Pisces: Perciformes) from West Africa, Zootaxa 4144 (1), pp. 124-130 : 126-127

Wallaceochromis gen. nov.

Differential Diagnosis. Lachrymal with four openings of laterosensory system; small chest scales; sixteen scales around caudal peduncle; upper lateral line clearly separated from dorsal fin base; teeth in both jaws unicuspid, a few teeth situated anterolaterally in the lower jaws with a curvature of the crown directed posteriorly and not buccally; no microbranchiospines; gill rakers on the outer row of the first ceratobranchial pachydermatous, transversely aligned, with a tuberculate and concave upper surface and a protracted distal tip; sexual dimorphism well developed: Males usually one third larger than females; in males first pelvic fin ray always longest, in females second (sometimes second and third) pelvic fin ray longer than first, giving the distal tip of the fin a rounded rather than pointed appearance. Snout pointed; dorsal head profile straight and sloping; low supraoccipital crest; ethmovomerine skull region slightly elongate and sloping at a low angle; it differs from Pelvicachromis in two contiguous tubular infraorbital bones (vs. three, with gap between 2nd and 3rd); 26–27 vertebrae with a tendency to higher abdominal vertebral counts (14–15 vs. 13–14); a more narrow interorbital region in adult specimens (maximum of 21.7–25.6% HL vs. 26.8–36.7% HL); seven or eight vertical dark bars on body, visible in several behavioral situations (vs. no such bars).

Included species: Wallaceochromis humilis (Boulenger, 1916) ; type species (fig. 2, 3A,B)

Wallaceochromis rubrolabiatus (Lamboj, 2004) (fig. 3C,D)

Wallaceochromis signatus (Lamboj, 2004) (fig. 3E,F)

Etymology. In honor of Alfred R. Wallace, co-founder of the theory of evolution and founder of biogeography; chromis, a common ending for African cichlids.

Distribution. The genus is restricted to Guinea, Sierra Leone, and western parts of Liberia, where it occurs strictly in freshwater ( Lamboj, 2004a). Wallaceochromis rubrolabiatus and W. signatus are only known from the Kolente River basin in Guinea, while W. humilis is found in the whole distribution area of the genus, including the Kolente River basin.