Topic
Benthochromis
About: Benthochromis is a research topic. Over the lifetime, 4 publications have been published within this topic receiving 94 citations.
Papers
TL;DR: The linearized tree analysis and the comparison of average sequence divergences to that of the remaining tribes of the H-lineage revealed a relatively recent but simultaneous proliferation of the Limnochromini, suggesting that the same environmental changes triggered the radiation of particular deepwater, benthic, pelagic, and littoral lineages.
Abstract: Lake Tanganyika harbors an enormous diversity of cichlid fish that stem from eight distinct ancestral lineages, which colonized the lake after its formation 9 to 12 million years ago. Six of twelve currently described tribes are assigned to the "H-lineage," an assemblage of exclusively mouthbrood-ing cichlids, all of which evolved during a short period of time during the course of the primary radiation of lacustrine species. Our study focuses on the deepwater tribe Limnochromini, comprising bi-parental mouthbrooders, and is based on phylogenetic analysis of two mitochondrial gene segments. We confirm the polyphyletic origin of the Limnochromini as they are defined to date, in that Gnathochromis pfefferi is placed among the Tropheini, whereas the genus Benthochromis is presented as an independent lineage. The remaining nine species were unambiguously resolved as monophyletic and should be redefined as the tribe Limnochromini. Concerning generic assignments, the genus Greenwoodochromis appeared as monophyletic, Limnochromis as paraphyletic, and the genera Reganochromis and Baileychromis as monophyletic sister genera. The linearized tree analysis and the comparison of average sequence divergences to that of the remaining tribes of the H-lineage revealed a relatively recent but simultaneous proliferation of the Limnochromini, suggesting that the same environmental changes triggered the radiation of particular deepwater, benthic, pelagic, and littoral lineages. By using a preliminary calibration of a molecular clock based on gamma-corrected amino acid distances of the NADH2 gene, the diversification of the Limnochromini could tentatively be dated to 2.9-3.5 MYA, coinciding with a period of aridification in East Africa between 2.5 and 3 MYA. The lack of geographic color morphs and the structural uniformity and resource scarcity of deepwater habitats suggest that competition and resource partitioning leading to differential trophic specialization promoted speciation within the Limnochromini, rather than an allopatric model.
90 citations
TL;DR: Investigating the monogenean fauna of Trematocara unimaculatum and Benthochromis horii found in the same deep-water habitat as the already known hosts of C. casuarinus found two new and non-resembling Cichlidogyrus species, which are new to science.
Abstract: Lake Tanganyika is the world’s second deepest lake. Its diverse cichlid assemblage offers a unique opportunity for studying a deep-water host-parasite model in freshwater. Low host specificity and a broad host range including representatives of the Bathybatini tribe in the only monogenean parasite described from this habitat, Cichlidogyrus casuarinus Pariselle, Muterezi Bukinga & Vanhove, 2015 suggest a link between lower specificity and lower host density. Conversely, high host specificity and species richness are reported for monogeneans of the lake’s littoral cichlids. We further investigated whether the deep-water environment in Lake Tanganyika is really monogenean species-depauperate by investigating the monogenean fauna of Trematocara unimaculatum (a representative of the tribe Trematocarini, the sister lineage of the Bathybatini) and Benthochromis horii, a member of the tribe Benthochromini, found in the same deep-water habitat as the already known hosts of C. casuarinus. Sclerotised structures of the collected monogenean individuals were characterised morphologically using light microscopy and morphometrics. Both examined cichlid species are infected by a single monogenean species each, which are new to science. They are described as Cichlidogyrus brunnensis n. sp., infecting T. unimaculatum, and Cichlidogyrus attenboroughi n. sp., parasitising on B. horii. Diagnostic characteristics include the distal bifurcation of the accessory piece in C. brunnensis n. sp. and the combination of long auricles and no heel in C. attenboroughi n. sp. In addition C. brunnensis n. sp. does not resemble C. casuarinus, the only species of Cichlidogyrus thus far reported from the Bathybatini. Also Cichlidogyrus attenboroughi n. sp. does not resemble any of the monogenean species documented from the pelagic zone of the lake and is among the few described species of Cichlidogyrus without heel. As two new and non-resembling Cichlidogyrus species are described from T. unimaculatum and B. horii, colonisation of the deep-water habitat by more than one morphotype of Cichlidogyrus is evident. Based on morphological comparisons with previously described monogenean species, parasite transfers with the littoral zone are possible. Therefore, parasites of pelagic cichlids in the lake do not seem to only mirror host phylogeny and the evolutionary history of this host-parasite system merits further attention.
10 citations
Journal Article•
TL;DR: It can be concluded that the highest diversity and abundance of ornamental cichlids was recorded from rocky and sandy habitats, and it is recommended that further study should be conducted to determine factors which may influence abundance and distribution of Ornamental fish in the lake.
Abstract: Diversity and abundance of ornamental cichlids of Lake Tanganyika was assessed in six habitats namely rocky, sandy, muddy, benthic, pelagic and surge water at Katonga fishing ground in Kigoma. Ornamental cichlids were collected using fishing net with a dimension of 10 m long x 1 m width and mesh size of 8 mm. eighteen species that are potential for export were observed and recorded. The highest diversity was recorded from sandy and rocky habitat (2.0) and the lowest in muddy habitat (0.0) respectively. Abundance of ornamental cichlids varied among habitats and species. Sandy habitat had the highest number (11) of ornamental cichlids predominated by Xenotilapia ochrogeny (30%) followed by Cyathofarynx fursifer (17.17%) and Benthochromis tricot (12.86%). Rocky habitat, had 10 species predominated by Tropheus kirschfleck (24.24%) followed by Goby cichlids (19.70%) and Tropheus brichardi (17.42%). On the other hand, muddy habitat was found to be monospecific in terms of ornamental fish species dominated by only one species, Cyathofarynx fursifer . It can be concluded that the highest diversity and abundance of ornamental cichlids was recorded from rocky and sandy habitats. It is recommended that further study should be conducted to determine factors which may influence abundance and distribution of ornamental fish in the lake. Keywords: Cichlids, Ornamental fish, Lake Tanganyika, Diversity
1 citations
TL;DR: Large males of the new species differ from those of congeneric species in terms of their body colour pattern and long pelvic fins.
Abstract: Benthochromis horii, a new cichlid species is described based on 19 type specimens from the deep waters of Lake Tanganyika It differs from its congeners by having smaller eyes and longer snout (eye length usually shorter than snout length v equal to or longer than snout length in Benthochromis tricoti and Benthochromis melanoides), and more dorsal fin rays (total number of spines and soft rays in dorsal fin usually 30 or 31 v usually 28 or 29 in B tricoti and B melanoides) Large males of the new species differ from those of congeneric species in terms of their body colour pattern and long pelvic fins This species has been confused with B tricoti and has been traded as an aquarium fish
Related Topics (5)
Performance Metrics
| Year | Papers |
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| 2018 | 1 |
| 2016 | 1 |
| 2008 | 1 |
| 2005 | 1 |