Référence originale dans:
- Tropheus sp. 'black', Konings et al., 1992, nom provisoire
Étymologie: The provisional name refers to the jet black background coloration. Pierre Brichard (unpublished data), who was working on the genus classification at the beginning of the 80's, had previously aptly named this species "black tail" Tropheus, as the tail and caudal peduncle are the only parts of the body which remain permanently black in adulthood.
Nom commun: Apart from "black Tropheus" or "black tailed Tropheus", several varieties got well known trade names, such as "Kaiser" (emperor), "orange Tropheus" "Kirschfleck" or "Doppelfleck Tropheus" (cherry-blotched or two-blotched) or, for the once most imported, "Brabant Tropheus".
Diagnose: All populations of this species show a jet black background coloration on the body, more or less barred with a broad yellow to orange-red band, in some varieties this bar is broken-up. However, as noticed by Pierre Brichard, only the tail remains black, as the rest of the body becomes light brown in frightened individuals. In my opinion, another, perhaps more important, diagnostic feature is constituted by the permanent loss of juvenile barred pattern, a peculiarity found only in the otherwise quite distinctive Tropheus duboisi. The upper iris is often red.
Taille: As most members of the genus, Tropheus sp. 'black' reaches 12-14 cm in TL (Total Length), though some northern varieties are reputedly smaller, but this may depend on the local ecological conditions; females are smaller.
Distribution: Tropheus sp. 'black' has a discontinuous distribution, with the main concentration situated in the northern sub-basin (north of the Ubwari peninsula) of Lake Tanganyika, and yet another one on the central Tanzanian coast. Interestingly, this broken distribution is more or less shared by other cichlids such as Tropheus duboisi and Neolamprologus leleupi. The southernmost location for Tropheus sp. 'black' is found at Cape Caramba on the western coast and it is interrupted on the eastern coast from Banza to Bulu Point, where the "Kirschfleck moorii" is found. If we include the "Kaiser I" Tropheus distribution it then extends its distribution north to Ikola.
Localités: Bulu Point (Tanzanie, indigène), Cape Caramba (République Démocratique du Congo, indigène), Katumbi Point (Tanzanie, non défini), Kifumbe (République Démocratique du Congo, indigène), Kigoma (Tanzanie, non défini), Kiriza (République Démocratique du Congo, indigène), Luagala Point (Tanzanie, non défini), Lubugwe Bay (Tanzanie, non défini), Lueba (République Démocratique du Congo, indigène), Luhanga (République Démocratique du Congo, indigène), Lumbye Bay (Tanzanie, indigène), Lyamembe Point (Tanzanie, non défini), Mabilibili (Tanzanie, indigène), Magara (Burundi, indigène), Mboko Island (République Démocratique du Congo, indigène), Miyako Point (Tanzanie, non défini), Mucansi (Burundi, indigène), Muzimu (République Démocratique du Congo, indigène), Nkwasi Point (Tanzanie, non défini), Pemba (République Démocratique du Congo, indigène), Siyeswe (Tanzanie, non défini).
Biotope: As other Tropheus of the moorii type, Tropheus sp. 'black' inhabits the upper rocky zone free of sediments.
Conservation: Tropheus sp. 'black' n'est pas évalué par l'Union Internationale pour la Conservation de la Nature dans la Liste rouge des espèces menacées. These fishes are abundant in their natural habitat, but in my opinion, are vulnerable for several reasons. First, cichlid collectors often choose exclusively most colorful specimens, which may have led to an impoverishment, especially in the "orange banded" Tropheus. Second, careless attitude ended in unwanted releases, for example of "Kaisers" from Ikola inside "Kirschfleck" populations, which led to an important amount of hybrids in some areas (hybridization, especially with feral animals, is a major threat in species conservation). Third, the dramatically overcrowded and politically unstable northern coasts of Lake Tanganyika are heavily polluted and intensely raked by starving people.
Alimentation: Feeds from the rocks algal bio-cover (aufwuchs). The squarish mouth with straight parallel jaws is identical to those of other members of the genus, except for Tropheus duboisi.
Reproduction: As other members of the genus, Tropheus sp. 'black' is a maternal mouth-brooder which produces a rather low number of eggs (usually from 6-20). In compensation, the pear-shaped eggs are among the largest in the family (7 mm in their longest diameter), giving birth to rather large and well developed young. The incubation period is basically 3 weeks, but often continues during several more weeks (up to 10), during which the young are released from time to time by the mother in sheltered areas and may feed inside their mother's mouth. The male does not take any part in the parental care and usually chases the female away immediately after the spawn, but in aquarium, he may tolerate her in the immediate surroundings of his territory.
Maintenance: Tropheus sp. 'black' does not differ markedly from its congeners in maintenance requirements in aquarium, except that it is probably among the most aggressive members of the genus, proportionally to its size (but this may vary considerably from one tank configuration to the next). In aquarium, males of all Tropheus species tend to defend their own territory, while linear hierarchies are found only in case of overcrowded small tanks. In order to observe their natural behavior in aquarium, Tropheus must be kept in small groups of several males and females in a large tank (at least 500 liters, but preferably 1000 liters or more) together with other tropheines such as Petrochromis or Simochromis. In smaller tanks, their murdering tendencies usually lead to the eradication of all subordinate males and females, unless the tank is markedly overcrowded. In some cases, when the sexes fit well together, they may be kept as a single pair, a situation which may last several months or years, until the male may finally kill his mate by frustration.
The water of the aquarium must be powerfully filtered, hard and alkaline (ph 8.2), with a temperature range around 23-26°C. These fishes must be given mainly ballast-rich foods, as they are very sensitive to intestinal problems. As for all members of the genus, Tropheus sp. 'black' tend to peck the fins of its tank-mates, especially when young, thus reducing sometimes considerably their extensions to unsightly extends.
Commentaires: It is now well-known that Tropheus sp. 'black' has been for a long time mistaken with Tropheus moorii. As Pierre Brichard never published his preliminary work on a subdivision of all Tropheus of the T. moorii type (all members of the genus except the distinctive T. duboisi). The denomination which he planned to use (Tropheus sp. 'black tail' was forgotten. Konings (1988) provisionally named this species Tropheus sp. aff. brichardi, and then Tropheus sp. 'black', which has now been adopted everywhere. Meanwhile, he decided to give a specific proposal for the southernmost variety from Ikola, the famous "Kaiser moorii" (also "Kaiser I", as the yellow banded Kiriza variety is also named "Kaiser II"). However, the Ikola "Kaiser" fully shows all diagnostic characteristic of the species, and giving it a specific status may end similarly for other races, such as the "Kirschfleck" from Bulu Point (which is done by Schupke, who treat both as different lineages). Considering the important homogeneity inside all "black-tailed" Tropheus, which differs from each other almost only by the shape of the yellow to orange red patches on the body, it is perhaps better to treat them as one species including some 5-10 subspecies.
Based on molecular data, Schupke (2003) did not include the orange Tropheus from Bemba (there is some dispute about the exact location, which is in fact Pemba) inside the "black" lineage, but this is not consistent with its external characteristics, which are probably of more importance than the differences in the molecular marker that was used.
- Konings, Ad. 1998. "Tanganyika Cichlids In Their Natural Habitat". Cichlid Press (crc00734)
- Konings, Ad & H.W. Dieckhoff. 1992. "Tanganyika Secrets". Cichlid Press. pp. 1-207 (crc01388)
- Konings, Ad. 1988. "Tanganyika Cichlids". Verduijn Cichlids, Holland. pp. 1-272 (crc01142)
- Schupke, Peter. 2003. "African Cichlids II, Tanganyika I, Tropheus". Aqualog (crc01827)
Tawil, Patrick. (juin 06, 2010). "Tropheus sp. 'black' ". Cichlid Room Companion. Consulté le août 07, 2020, de: https://cichlidae.com/species.php?id=156&lang=fr.