Cytotaxonomy of Gallinula melanops (Gruiformes, Rallidae): Karyotype evolution and phylogenetic inference

Abstract Although Rallidae is the most diverse family within Gruiformes, there is little information concerning the karyotype of the species in this group. In fact, Gallinula melanops, a species of Rallidae found in Brazil, is among the few species studied cytogenetically, but only with conventional staining and repetitive DNA mapping, showing 2n=80. Thus, in order to understand the karyotypic evolution and phylogeny of this group, the present study aimed to analyze the karyotype of G. melanops by classical and molecular cytogenetics, comparing the results with other species of Gruiformes. The results show that G. melanops has the same chromosome rearrangements as described in Gallinula chloropus (Clade Fulica), including fission of ancestral chromosomes 4 and 5 of Gallus gallus (GGA), beyond the fusion between two of segments resultants of the GGA4/GGA5, also fusions between the chromosomes GGA6/GGA7. Thus, despite the fact that some authors have suggested the inclusion of G. melanops in genus Porphyriops, our molecular cytogenetic results confirm its place in the Gallinula genus.

摘要：尽管秧鸡科（Rallidae）是鹤形目（Gruiformes）中最多样化的科，但关于该科物种染色体组型的研究信息极为有限。实际上，巴西发现的黑水鸡（Gallinula melanops），作为秧鸡科的一员，是少数进行过细胞遗传学研究的物种之一，但仅限于传统的染色和重复DNA定位，结果显示2n=80。因此，为了解析该群体的染色体组型进化和系统发育，本研究旨在通过经典和分子细胞遗传学方法分析G. melanops的染色体组型，并将结果与其他鹤形目物种进行比较。研究结果揭示，G. melanops具有与Gallinula chloropus（ Fulica分支）中描述的相同的染色体重排，包括GGA（Gallus gallus）的祖先染色体4和5的分裂，以及GGA4/GGA5的结果片段之间的融合，此外还有GGA6/GGA7染色体之间的融合。因此，尽管一些作者建议将G. melanops归入Porphyriops属，但我们的分子细胞遗传学结果证实了其在Gallinula属中的地位。