Daniels Savel R, Stewart Barbara A, Gouws Gavin, Cunningham Michael, Matthee Conrad A
Zoology Department, University of Stellenbosch, Private Bag X1, 7602, Matieland, South Africa.
Mol Phylogenet Evol. 2002 Dec;25(3):511-23. doi: 10.1016/s1055-7903(02)00281-6.
The phylogenetic relationships among the southern African freshwater crab species were examined using partial sequence data from three mitochondrial genes (12S rRNA, 16S rRNA, and mtDNA COI) 26 morphological characters and 14 allozyme loci. The aims of the present study were firstly to determine whether freshwater crab species that live in the same geographic region share a close phylogenetic relationship. Secondly, to investigate whether hybridizing species are genetically closely related and thirdly, to test for the validity of subgenera based on the genetic data sets. Phylogenetic analysis based on sequence data revealed largely congruent tree topologies and some associations had consistently high bootstrap support, and these data did not support Bott's subgeneric divisions. The morphological data were less informative for phylogenetic reconstruction while the allozyme data generally supported patterns recovered by the sequence data. A combined analysis of all the data recovered two monophyletic clades, one comprised of small-bodied mountain stream species and the other clade consisting of large-bodied riverine species. The combined analyses reflected clear biogeographic patterning for these river crabs. In addition, there was a clear correlation between genetic distance values and the ability of sympatric species to hybridize.
利用来自三个线粒体基因（12S rRNA、16S rRNA和mtDNA COI）的部分序列数据、26个形态特征和14个等位酶位点，研究了南部非洲淡水蟹物种之间的系统发育关系。本研究的目的，一是确定生活在同一地理区域的淡水蟹物种是否具有密切的系统发育关系；二是调查杂交物种在基因上是否密切相关；三是基于基因数据集检验亚属的有效性。基于序列数据的系统发育分析揭示了基本一致的树形拓扑结构，一些关联具有始终较高的自展支持率，而这些数据并不支持博特的亚属划分。形态学数据对系统发育重建的信息量较少，而等位酶数据总体上支持序列数据所恢复的模式。对所有数据的综合分析得到了两个单系类群，一个由体型较小的山间溪流物种组成，另一个类群由体型较大的河流物种组成。综合分析反映了这些河蟹明显的生物地理格局。此外，遗传距离值与同域物种杂交能力之间存在明显的相关性。
