. Bulletin of the British Museum (Natural History). Zoology . 58 P. H. GREENWOOD decurved dorsal profile to the preorbital face of the neurocranium (giving the orbital margiii a near-rounded circumference), the high cranial vault and the relatively short ethmovomerine region. The premaxillary ascending process is shorter than the dentigerous arm of the bone, and the lower jaw (dentary plus articular) is neither foreshortened nor elongate. The lower pharyngeal bone is not noticeably thickened, and its equilateral denti- gerous surface is covered by fairly well-spaced rows of cuspid
. Bulletin of the British Museum (Natural History). Zoology . 58 P. H. GREENWOOD decurved dorsal profile to the preorbital face of the neurocranium (giving the orbital margiii a near-rounded circumference), the high cranial vault and the relatively short ethmovomerine region. The premaxillary ascending process is shorter than the dentigerous arm of the bone, and the lower jaw (dentary plus articular) is neither foreshortened nor elongate. The lower pharyngeal bone is not noticeably thickened, and its equilateral denti- gerous surface is covered by fairly well-spaced rows of cuspidate and laterally com- pressed teeth. Teeth in the median rows are usually a little coarser than those situated laterally (Text-fig. 30A).. 3 mm Fig. 30. Haplochromis bloyeti. A : Lower pharyngeal bone in occlusal view. B : Outer row teeth from the premaxilla ; viewed anterolateral^. Scale = imm.) The outer jaw teeth in H. bloyeti are unequally bicuspid, the cusps triangular in outline (Text-fig. 30B) ; the inner teeth are small and tricuspid, and are arranged in not more than three rows in either jaw. Usually a few unicuspid teeth occur pos- teriorly in the outer row of the premaxilla, and in larger fishes (> 80 mm long) a few unicuspids are intercalated with the bicuspids anteriorly and anterolaterally in both jaws. Among extant Lake Victoria endemic species, H. pallidas has a syncranium and dentition virtually identical with that of H. bloyeti (see Text-figs 31-33), and there are several other similarly generalized species known. Having established the anatomical nature of a generalized species, each trophic group (see pp. 58-80) will be considered in turn, probable phyletic lineages (based on shared specialized characters, synapomorphy) will be delimited and, where possible, interrelated. The insectivorous species Typically generalized skull, jaws and dentition are found in five species (H. pallidas [Text-figs 32 and 33], H. macrops [Text-figs 32 and 33], H. lacrimo
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