Colonisation du Bas Congo par Steatocranus et Nanochromis
Posté : 12 avr. 2013 18:19
Pour les autres passionnés comme moi du genre Nanochromis, mais aussi Steatocranus, il en faut bien pour tous les goûts, voici un article fort intéressant sur ces 2 genres, montrant entre autres les relations des différentes espèces dans les 2 genres et leurs répartitions en milieu naturel.
http://www.plosone.org/article/info%3Ad ... ne.0022380
Les Figures illustrant le sujet sont expressément grandes, pour pouvoir lire toutes les informations des dendrogrammes.
Grâce à cet article on savoir qu’il existe 27 espèces ou formes de Steatocranus, selon les auteurs :
« S. » irvinei
S. bleheri
S. casuarius
S. cf. aff. « Inga »
S. cf. aff. tinanti
S. cf. aff. tinanti « intermediate »
S. cf. aff. tinanti "ultraslender"
S. cf. gibbiceps
S. gibbiceps
S. glaber
S. mpozoensis
S. mpozoensis "Boma"
S. mpozoensis "Mpozo"
S. rouxi
S. sp. « ‘bulky head »’
S. sp. « ‘dwarf »’
S. sp. « ‘Kisangani »’
S. sp. « ‘Kwilu »’
S. sp. « ‘Maluku »’
S. sp. « ‘Mbandaka »’
S. sp. « ‘Nki »’
S. sp. « ‘red eye »’
S. sp. « Dja »
S. sp. « Lefini »
S. sp. aff. casuarius « ‘brown pearl »’
S. tinanti
S. ubanguiensis
Et 10 espèces de Nanochromis :
N_consortus
N_minor
N_nudiceps
N_parilus
N_sp_ « ‘Mbandaka »’
N_sp_ « ‘Ndongo »’
N_splendens
N_teugelsi
N_transvestitus
N_wickleri
Et que chez les Congochromis il existe :
C_dimidiatus
C_pugnatus
C_robustus
C_sabinae
C_sabinae sp. « Bloody Mary »
C_sabinae sp. « LuiKotale »
C_sabinae sp. « Yambula »
C_squamiceps
C_squamiceps sp. « Amba »
Et quelques illustrations, pour ceux ne voulant pas tout lire :
Figure 1. Location map of sampling sites.
Circles correspond to Steatocranus and squares to Nanochromis sampling sites. The filled circle and square mark the location of unsamples species. The half filled circle indicate that the species was included in the sequence but not in the AFLP analysis. Letters correspond to non-lower-Congo species distributions : (a) Nanochromis parilus, (b) N. teugelsi, (c) N. nudiceps, (d) N. transvestitus, N. wickleri, (e) N. sp. « Mbandaka» (f) N. sp. « Ndongo» (A) S. sp. « dwarf », S. sp. « bulky head », S. bleheri, S. sp. « Maluku » (B) S. sp. « red eye» (C) S. sp. « Kwilu » (D) S. rouxi, (E) S. sp. « Mbandaka », S. sp « Maluku » (F) S. ubanguiensis, (G) S. sp. « Kisangani » and (H) S. sp. « Nki. Sampling locations along the lower Congo are presented in larger scale and marked by red circles. Numbers along the lower Congo correspond to the sample site legend in the lower right side. White background highlights the territory of the Democratic Republic of Congo.
doi:10.1371/journal.pone.0022380.g001
Figure 2. Phylogenetic trees based on nc- and mt-datasets.
The datasets comprises mitochondrial sequences of ND2 and over 2000 AFLP markers for (a) Steatocranus and (b) Nanochromis. Black numbers at nodes refer to bootstrap-values (BS, 1000 pseudo-replicates) of the ML run (right side) or the neighbour joining tree (left side). Filled circles represent a 100% BS support. Major groups within the phylogeny are marked with coloured frames. Species that are placed differently in AFLP and mt-trees are marked in red. The red frames in Nanochromis trees indicate differences in sistergroup-ralationships.
doi:10.1371/journal.pone.0022380.g002
Figure 3. Chronogram showing divergence time estimates for Steatocranus and Nanochromis.
The chronogram was calculated based on the ML tree. A partitioned Bayesian analysis implemented in BEAST was used to estimate divergence times. Time constraints were used following Schwarzer et al. [18] : A1 53–84 mya (uniform prior), published age estimate based on non-cichlid fossils [35] and O1 5.98 mya (lower bound), the age estimate for Oreochromis lorenzoi† [34]. The chronogram shows 95% credibility intervals (HPC, green bars). For nodes marked with letters, age estimates (95% HPC and mean heights) are given in Table 1. The asterisk marks the non-endemic lower Congo clade including N. parilus and N. teugelsi. Nanochromis parilus is distributed in the lower Congo but can also be found at Maluku upstream of Malebo pool. For simplification clear monophyletic groups were combined and shown as triangles.
doi:10.1371/journal.pone.0022380.g003
Figure 4. Potential colonization scenarios for Steatocranus and Nanochromis.
Potential colonization scenarios are shown separately for both genera. The red arrows indicate potential dispersal routes of Steatocranus and Nanochromis precursors. Non-lower Congo taxa are written in black. Current distribution ranges of the major lower Congo phylogenetic clades (see Fig. 2) are represented by different kinds of dotted lines (see figure legend). Clade 1 (Steatocranus) : S. cf. casuarius species pair, clade 2 (Steatocranus) : S. cf. tinanti/ S. cf. gibbiceps/ S. glaber and S. mpozoensis, clade1 (Nanochromis): N. splendens and N. consortus, and clade 2 (Nanochromis): N. parilus. The trisection of the lower Congo is shown in combination with sampling sites (indicated by red dots) along the lower Congo. The upper part of the Congo River is presented highly simplified for a better understanding.
doi:10.1371/journal.pone.0022380.g004
http://www.plosone.org/article/info%3Ad ... ne.0022380
Les Figures illustrant le sujet sont expressément grandes, pour pouvoir lire toutes les informations des dendrogrammes.
Grâce à cet article on savoir qu’il existe 27 espèces ou formes de Steatocranus, selon les auteurs :
« S. » irvinei
S. bleheri
S. casuarius
S. cf. aff. « Inga »
S. cf. aff. tinanti
S. cf. aff. tinanti « intermediate »
S. cf. aff. tinanti "ultraslender"
S. cf. gibbiceps
S. gibbiceps
S. glaber
S. mpozoensis
S. mpozoensis "Boma"
S. mpozoensis "Mpozo"
S. rouxi
S. sp. « ‘bulky head »’
S. sp. « ‘dwarf »’
S. sp. « ‘Kisangani »’
S. sp. « ‘Kwilu »’
S. sp. « ‘Maluku »’
S. sp. « ‘Mbandaka »’
S. sp. « ‘Nki »’
S. sp. « ‘red eye »’
S. sp. « Dja »
S. sp. « Lefini »
S. sp. aff. casuarius « ‘brown pearl »’
S. tinanti
S. ubanguiensis
Et 10 espèces de Nanochromis :
N_consortus
N_minor
N_nudiceps
N_parilus
N_sp_ « ‘Mbandaka »’
N_sp_ « ‘Ndongo »’
N_splendens
N_teugelsi
N_transvestitus
N_wickleri
Et que chez les Congochromis il existe :
C_dimidiatus
C_pugnatus
C_robustus
C_sabinae
C_sabinae sp. « Bloody Mary »
C_sabinae sp. « LuiKotale »
C_sabinae sp. « Yambula »
C_squamiceps
C_squamiceps sp. « Amba »
Et quelques illustrations, pour ceux ne voulant pas tout lire :
Figure 1. Location map of sampling sites.
Circles correspond to Steatocranus and squares to Nanochromis sampling sites. The filled circle and square mark the location of unsamples species. The half filled circle indicate that the species was included in the sequence but not in the AFLP analysis. Letters correspond to non-lower-Congo species distributions : (a) Nanochromis parilus, (b) N. teugelsi, (c) N. nudiceps, (d) N. transvestitus, N. wickleri, (e) N. sp. « Mbandaka» (f) N. sp. « Ndongo» (A) S. sp. « dwarf », S. sp. « bulky head », S. bleheri, S. sp. « Maluku » (B) S. sp. « red eye» (C) S. sp. « Kwilu » (D) S. rouxi, (E) S. sp. « Mbandaka », S. sp « Maluku » (F) S. ubanguiensis, (G) S. sp. « Kisangani » and (H) S. sp. « Nki. Sampling locations along the lower Congo are presented in larger scale and marked by red circles. Numbers along the lower Congo correspond to the sample site legend in the lower right side. White background highlights the territory of the Democratic Republic of Congo.
doi:10.1371/journal.pone.0022380.g001
Figure 2. Phylogenetic trees based on nc- and mt-datasets.
The datasets comprises mitochondrial sequences of ND2 and over 2000 AFLP markers for (a) Steatocranus and (b) Nanochromis. Black numbers at nodes refer to bootstrap-values (BS, 1000 pseudo-replicates) of the ML run (right side) or the neighbour joining tree (left side). Filled circles represent a 100% BS support. Major groups within the phylogeny are marked with coloured frames. Species that are placed differently in AFLP and mt-trees are marked in red. The red frames in Nanochromis trees indicate differences in sistergroup-ralationships.
doi:10.1371/journal.pone.0022380.g002
Figure 3. Chronogram showing divergence time estimates for Steatocranus and Nanochromis.
The chronogram was calculated based on the ML tree. A partitioned Bayesian analysis implemented in BEAST was used to estimate divergence times. Time constraints were used following Schwarzer et al. [18] : A1 53–84 mya (uniform prior), published age estimate based on non-cichlid fossils [35] and O1 5.98 mya (lower bound), the age estimate for Oreochromis lorenzoi† [34]. The chronogram shows 95% credibility intervals (HPC, green bars). For nodes marked with letters, age estimates (95% HPC and mean heights) are given in Table 1. The asterisk marks the non-endemic lower Congo clade including N. parilus and N. teugelsi. Nanochromis parilus is distributed in the lower Congo but can also be found at Maluku upstream of Malebo pool. For simplification clear monophyletic groups were combined and shown as triangles.
doi:10.1371/journal.pone.0022380.g003
Figure 4. Potential colonization scenarios for Steatocranus and Nanochromis.
Potential colonization scenarios are shown separately for both genera. The red arrows indicate potential dispersal routes of Steatocranus and Nanochromis precursors. Non-lower Congo taxa are written in black. Current distribution ranges of the major lower Congo phylogenetic clades (see Fig. 2) are represented by different kinds of dotted lines (see figure legend). Clade 1 (Steatocranus) : S. cf. casuarius species pair, clade 2 (Steatocranus) : S. cf. tinanti/ S. cf. gibbiceps/ S. glaber and S. mpozoensis, clade1 (Nanochromis): N. splendens and N. consortus, and clade 2 (Nanochromis): N. parilus. The trisection of the lower Congo is shown in combination with sampling sites (indicated by red dots) along the lower Congo. The upper part of the Congo River is presented highly simplified for a better understanding.
doi:10.1371/journal.pone.0022380.g004
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