|
|
|
Lake Tanganyika cichlids — species, locations & maps
Lake Tanganyika cichlids — species, locations & maps
tanganyika.si
Lake Tanganyika cichlids — species, locations & maps.
All images are used with permission of the authors. Unauthorized use is prohibited.
Quick links
Contact
© tanganyika.si
Habitats may form contact zones with adjacent Tropheus assemblages, particularly in regions where different color forms or closely related species meet, resulting in mixed populations and, in some areas, natural hybridization.
At both ends of its range, T. moorii occurs alongside other Tropheus species. In Zambia, between Kala Bay and Chilanga, it shares habitat with T. sp. 'red'. In northern Tanzania, it co-occurs with T. sp. 'kipili' along an extended stretch of coastline between Katale Bay and Sangamwisha Bay and in the Mtosi Bay area.
Water chemistry is of critical importance. The pH must be above 7.5 (approximately 7.5 to 9.5). Temperature should be kept consistently between 24 and 27°C and must never exceed 29°C, as this can be fatal. Higher temperatures increase oxygen demand while simultaneously reducing dissolved oxygen levels. In Lake Tanganyika, the upper 40 m of water is very clear and rich in oxygen; therefore, the aquarium should also be well oxygenated using air pumps, filter outlets directed toward the surface, or circulation pumps that enhance surface agitation.
Tropheus are highly sensitive to ammonia, nitrite, and nitrate. The filtration system must therefore be powerful and biologically mature. Ammonia and nitrite cause immediate poisoning, while elevated nitrate levels lead to a gradual deterioration of health. Regular weekly water changes of 30–50% are essential, and replacement water should also be well oxygenated.
It is practically impossible to recreate the natural environment of Tropheus in an aquarium, as this would require an extremely large system. In the wild, most adult Tropheus are territorial; similarly, in the aquarium one or a few territorial males occupy defined areas, leaving limited space for other males and females. Because food availability in the aquarium is higher than in nature, non-territorial individuals tend to suppress the need to establish separate feeding territories.
Tropheus are best maintained in relatively large groups of approximately 15 to 25 individuals. In such groups, there may be several males, but there should be at least three to four females per male. Typically, only one male becomes dominant, occupies a territory, and is the only individual that spawns.
In community aquaria, somewhat smaller groups may also be kept. Suitable tank mates include other herbivorous Tanganyikan cichlids, such as smaller Petrochromis species, goby cichlids (Eretmodus, Tanganicodus, and Spathodus)...
Different geographic variants of the same Tropheus species should never be kept together due to the high risk of hybridization. Different Tropheus species may be kept together, preferably those that naturally occur at the same locations. For example, T. duboisi can generally be housed with other Tropheus species, although its lower aggressiveness often makes a species-only aquarium the better choice.
When establishing a group, it is best to introduce a larger number of juveniles so territories develop gradually as the fish grow. Introducing adults often results in extremely violent territorial conflicts. Adding Tropheus to an already established group with defined territories is also very difficult.
High-protein foods must be strictly avoided, as they can be lethal. Tropheus have a very long digestive tract adapted to a low-protein diet, and excessive protein intake can quickly lead to the condition known as bloat, to which they are extremely susceptible.
Adult fish should be fed once per day, only as much as they can consume within two minutes. Feeding can also be divided into several smaller meals per day, provided the total daily amount remains the same.
A receptive female responds to the male’s courtship displays and follows him to his territory. Spawning usually occurs in the calmest part of the territory, often on a gently sloping surface. Eggs are laid one at a time, immediately taken into the female’s mouth, and fertilized by the male during this process.
Eggs are relatively large (approximately 5–7 mm), resulting in small broods of about 6–16 eggs. The female carries the developing fry for around 24–26 days, after which she gradually releases them and guards them for several days. The male plays no role in brood care and often drives the female away immediately after spawning.
Unlike many other mouthbrooding cichlids, female Tropheus continue to feed while carrying fry. In some species, females may accept food without swallowing it, with the food consumed only by the fry, whereas in other species females feed normally together with the fry.
In the aquarium, limited space usually allows only a few, or even a single, dominant male to hold a territory, from which all other cichlids are chased away. Aggression is strongest toward conspecifics, while other species are typically tolerated to a greater extent. Due to pronounced intraspecific aggression, Tropheus should be kept in larger groups to distribute aggression among more individuals.
Juveniles show very thin vertical bars on the body and face, which often become interrupted or reduced in adults. Spots matching the color of the lateral and head bars are visible on the faces of juveniles and usually develop into tiny dots covering the head in adults. The dorsal fin is light in coloration.
A broad chest band is absent; instead, a light whitish to orange patch is often present on the flanks.
T. moorii was among the first Tanganyikan cichlids described (Boulenger, 1898), yet major aspects of its identity remain debated. Ad Konings discussed this explicitly in 2012 in an article titled “Do we really know T. moorii?”. The precise type locality has been considered uncertain, with suggestions ranging from the Mpulungu area to (possibly more likely) the Cape Chaitika region.
Numerous geographic variants are recognized within what is currently referred to as T. moorii. In Zambia, the well-known aquaristic form “Ilangi” originates from the Kala Bay–Chilanga region where T. sp. 'red' also occurs. According to Ad Konings, Linangu Point (just south of Kala Bay) was an early collection locality for many “Ilangi”, but Toby Veall reported that only T. sp. 'red' is now found there; “Ilangi” is suggested to have been overcollected locally, while it is still present somewhat further north in Kala Bay. Based on this, the so-called Yellow Rainbow moorii known in the hobby as “Linangu moorii” may not originate from Linangu Point. Exact localities are also described as unclear for some other Yellow Rainbow forms (Musanga, Nkonde, Chilambo), but are placed generally around the Inangu Peninsula.
Additional observations and genetic work are cited as supporting a complex contact zone in parts of the Zambian range. Evert van Ammelrooy reportedly photographed an “Ilangi”-like fish from Kala Bay also at Sumbu Island, far west of Kala Bay. Sefc (2017) concluded from molecular analyses that the area between Ndole Bay and the Lufubu River represents a hybrid zone, consistent with different Tropheus types occurring at the same locality. Examples given include Sumbu (individuals resembling T. sp. 'red' alongside others resembling “Ilangi”) and Cape Kapchese (where T. sp. 'red' occurs together with a more yellow variant known as “Golden Kazumba”).
In northern Tanzania, no hybridization has been reported between T. moorii and T. sp. 'kipili' in the stretch between Katale Bay and Sangamwisha Bay. In contrast, hybridization is reported from the Mtosi Bay area, where African Diving collected mixed groups in 2003 that included yellow and red T. moorii (the red form referred to as “Red Namansi”) together with T. sp. 'Kipili'. Some individuals could not be clearly assigned to either form and were interpreted as natural hybrids. It was further suggested that the red dorsal fin observed in “Red Namansi” may indicate genetic exchange with T. sp. 'kipili', whose juveniles are described as reddish.
A Tanzanian "Murago" form was previously treated as a T. moorii variant, as molecular and morphological analyses placed it closer to T. moorii than to T. sp. 'limespot' (T. sp. 'maculatus'). In a 2019 revision context, it is mentioned as a possible distinct species (referred to as T. sp. 'murago'). To avoid confusion with a DR Congo "Murago", the Tanzanian form from the Wampembe area is referenced under the name Tropheus sp. 'murago tanzania'. On tanganyika.si this taxon is likewise treated as a distinct species, separate from T. moorii.
Photo gallery