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''Paratilapia'' is a genus of cichlids generally restricted to Madagascar. These are large, dark cichlids densely covered in light spots. An additional very poorly known species from the Congo River basin in mainland Africa is sometimes also placed in the genus, but this is highly questionable and arguably it is better placed in the "wastebasket genus" ''Haplochromis'' for the time being.〔Greenwood (1979). ''Towards a phyletic classification of the 'genus' Haplochromis (Pisces, Cichlidae) and related taxa.'' Bulletin of the British Museum (Natural History) Zoology 35(4): 265-322〕〔 == Taxonomy == Phylogenetic analsysis of DNA sequence and morphological data have hitherto been unable to resolve the relationships of the genus to satisfaction. For example sequence data from mtDNA 16S rRNA and COI disagrees regarding its placement,〔 (2004): Molecular phylogeny and biogeography of the Malagasy and South Asian cichlids (Teleostei: Perciformes: Cichlidae). ''Molecular Phylogenetics and Evolution'' 30(3): 599–614. (HTML abstract)〕 and the standard hypothesis among cichlids - that this is due to hybridization effects - can obviously not apply here as both genes are mitochondrial and affected by hybrid introgression in the same way. In any case, ''Paratilapia'' tends to occupy a position between African subfamilies such as the Ptychochrominae and the Indo-Malagasy clade comprising Etroplinae and Ptychochrominae in most analyses, and this may well be correct. If so, its ancestors must have separated from those of all other living cichlids in the Mesozoic. They most probably were already a distinct lineage by the Turonian (c.90 mya), as the Indo-Malagasy clade must have originated before the split of Madagascar from the Indian Platewhich commenced then and was finished by the end of the Cretaceous.〔 Consequently, they would have to be classified as a subfamily of their own, Paratilapiinae. While currently included in this genus, ''P. toddi'' probably does not belong here. Correct placement is uncertain.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Paratilapia」の詳細全文を読む スポンサード リンク
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