Taxonomy & naming
The species was described by the Belgian-British ichthyologist George Albert Boulenger in 1906 as Pelmatochromis spekii, from material collected at Bunjako on the northern shore of Lake Victoria (Victoria Nyanza), Uganda. Boulenger named it in the same 1906 paper in which he honoured Speke's travelling companion James Augustus Grant with Haplochromis granti. Peter Humphry Greenwood, who spent decades untangling the Victoria flock, selected a lectotype (BMNH 1906.5.30.296, in the Natural History Museum, London) in 1967 and transferred the species to the catch-all genus Haplochromis. In his later systematic revisions of the lake's predatory cichlids, Greenwood (1980) erected the genus Harpagochromis for the large, deep-bodied piscivores with strong recurved jaw teeth, and spekii is routinely listed under that name — the Cichlid Room Companion and much of the field literature treat it as Harpagochromis spekii. That generic split has never been universally accepted: the morphological diagnoses overlap, molecular work has shown the Lake Victoria 'superflock' to be extremely young and genetically near-uniform, and the Catalog of Fishes and FishBase retain the conservative combination Haplochromis spekii. We keep the species under the Haplochromis heading here for consistency while noting that Harpagochromis is the genus used in most modern Lake Victoria treatments. The genus belongs to the subfamily Pseudocrenilabrinae, tribe Haplochromini.
Morphology
Haplochromis spekii is one of the larger members of the flock, reaching about 8.5 in in standard length — big by haplochromine standards, where most species mature well under 4.5 in. It has the build of a haplochromine fish-hunter: an elongate, moderately deep and laterally compressed body, a large head, and big jaws set with the strong, unequally bicuspid to nearly conical and recurved teeth that characterise the piscivorous Harpagochromis group and let it seize and hold other fish. No colour photograph of a confirmed wild specimen is in general circulation, and the original and revisionary descriptions are the main guide to its appearance; like related Victorian piscivores, breeding males would have carried the metallic blue-grey to greenish flank sheen and an anal fin marked with orange-yellow ocelli ('egg spots'), while females and non-breeding fish are plainer silvery-brown with darker vertical bars or blotches. As in essentially all haplochromines, the species is sexually dimorphic and dichromatic: males are the brighter, more strongly marked sex and males reach the larger size. Precise meristic and morphometric details rest on the type series and Greenwood's revisions rather than on any large modern sample.
Habitat
The species is endemic to the Lake Victoria basin — the lake itself and the Victoria Nile draining north from it — within the Lake Victoria Basin freshwater ecoregion, spanning the riparian waters of Tanzania, Uganda and Kenya. FishBase records it from a depth range of about 10–30 ft, placing it in the sub-littoral and shallow offshore zone rather than the shoreline shallows or the deep profundal. It is reported over hard (mostly) and soft organic substrates, occurring in sheltered areas and, less often, in exposed situations. Lake Victoria is a large, shallow, warm equatorial lake; its open waters are circumneutral to alkaline, typically running pH near 7.2 in inshore waters up to roughly 9 in productive open water, with surface temperatures generally between about 23 and 27 degrees C year-round. The lake has changed profoundly within living memory — once-clear water has become turbid and seasonally deoxygenated at depth through eutrophication — and the predatory haplochromines of the open and sub-littoral bottom, this species among them, were tied to exactly the habitats most transformed since the mid-twentieth century.
Feeding
Haplochromis spekii is a piscivore — a fish-eater. FishBase records that it 'feeds on small fishes' and places it at a trophic level of about 4.2, near the top of the haplochromine food web, and its jaw and tooth structure is that of the predatory Harpagochromis assemblage built to grab and swallow other fishes whole. In the trophic classification of the Lake Victoria flock developed by van Oijen and colleagues and by the Haplochromis Ecology Survey Team (HEST), the lake's haplochromines sort into guilds — detritivores, zooplanktivores, insectivores, molluscivores and piscivores — and spekii sits squarely in the piscivore guild, the group of relatively large predators that preyed heavily on smaller haplochromines and juvenile fish. (Some general write-ups loosely call it a molluscivore or invertivore; the primary FishBase and revisionary evidence points to piscivory, and we follow that here.) Within the intact ecosystem this guild occupied the predator tier that the introduced Nile perch would later usurp.
Mating
No courtship account specific to Haplochromis spekii has been published, and what can be said is inferred from the very consistent reproductive biology of the haplochromine flock. These are polygynous, maternal mouthbrooders with no lasting pair bond: a male establishes and defends a temporary territory or court, displays to ripe females with lateral spreading of the fins and presentation of the egg-dummy ocelli on his anal fin, and spawns with a succession of females. The male's role ends at spawning; he provides no care. Breeding is the period of strongest male coloration and of male-male aggression over courting space, and outside of it the fish are far less territorial. For a sub-littoral predator like this one, spawning would have taken place over the bottom in the species' normal depth band rather than at a built nest, the female taking the eggs into her mouth almost immediately.
Breeding
Haplochromis spekii is a maternal mouthbrooder, as FishBase records and as is the rule throughout the Lake Victoria haplochromines. The female collects the eggs into her mouth at or just after spawning — drawn to fertilise them by the male's anal-fin egg-dummies in the classic haplochromine fashion — and incubates the developing clutch in her buccal cavity for roughly two to three weeks, taking little or no food during that time, before releasing free-swimming fry that may continue to shelter in her mouth when threatened. There are no published clutch counts for this species specifically; Lake Victoria haplochromines are comparatively low-fecundity mouthbrooders, congeners typically carrying on the order of a few dozen up to around a hundred relatively large eggs, with larger-bodied species toward the upper end of that range. This small-clutch, high-investment strategy is one reason the flock's species are vulnerable to a sustained new predator: there is no flood of eggs to absorb the losses.
In the aquarium
Haplochromis spekii is essentially not an aquarium fish. It is not present in the ornamental trade, no aquarium-maintenance information exists for it, and given that the Catalog of Fishes flags the species as possibly extinct, it may no longer exist to be kept at all. Almost everything an aquarist would want to know therefore has to be reasoned from close relatives rather than from experience with this fish.
A handful of Lake Victoria haplochromines — mostly small, brightly coloured zooplanktivores and rock-dwellers such as the so-called 'Kenya gold', the 'flameback' and various Pundamilia and Astatotilapia — are kept and bred by a dedicated conservation-minded segment of the hobby, often in cooperation with public aquaria and species-survival programmes. A large piscivore like spekii would be a different and far more demanding proposition: it would need a long tank measured in hundreds of litres, hard, alkaline, warm water (pH around 7.5 to 8.5, roughly 24 to 27 degrees C) matching Lake Victoria's chemistry, robust filtration, and a diet of whole foods appropriate to a fish-eater. Critically, it could not be safely housed with anything small enough to swallow, which rules out the very community of small Victorian haplochromines that hobbyists most want to keep. The honest summary is that this species is of museum and conservation interest, not aquarium interest; if you want to support Lake Victoria cichlids in the hobby, the productive route is the captive-breeding programmes for the surviving smaller species rather than this predator.
Conservation
The IUCN Red List assesses Haplochromis spekii as Data Deficient (assessed 31 March 2010 by F. Witte and M.P. de Zeeuw), reflecting that too little is known about its current population and distribution to assign a threat category with confidence; the population trend is listed as unknown. The Catalog of Fishes goes further and annotates the species' distribution as 'extinct.' That ambiguity is itself the story. From the late 1970s the introduced Nile perch (Lates niloticus) erupted across Lake Victoria, and over the 1980s the sub-littoral and offshore haplochromines — an estimated 200 species — collapsed almost completely; eutrophication and a commercial trawl fishery compounded the predation. Studies of the Mwanza Gulf flock by Witte, van Oijen and colleagues showed the guilds declined at different rates, and the relatively large piscivores, the group to which spekii belongs, were among the very first to disappear from the catches, alongside the insectivores and molluscivores. When Nile perch was itself heavily fished in the 1990s, the small detritivores and zooplanktivores staged a partial recovery — but the large predators, slower to breed and directly out-competed, did not rebound in the same way. Whether spekii survives in a refuge somewhere in the basin or is already gone is precisely what 'Data Deficient' leaves open. The threats the assessment records — invasive species, eutrophication from domestic, industrial and agricultural effluent, and fishing pressure — remain the defining pressures on what is left of the Lake Victoria cichlid flock.