Speciation, karyotypic differentiation, and hybrid zones in the Leibunum curvipalpe group (Arachnida, Opiliones)

由11个种(L.hiraiwai、L.montanum、L.kohyai、L.sadoense、L.implum、L.hiasai、L.hikocola、L.curvipalpe、L.tohokuense、L.lobosum和L.manubriatum)组成的曲纹盘藻群在种间和种内均表现出较大的核型变异。此外，在该组中的两个物种中，也已知存在多倍体小种。研究了核型分化的地理模式和染色体杂交带在该群体物种形成过程中的作用。所获得的主要结果如下。1.在本州初谷山东段发现了2n=18~20/22的毛叶连翘染色体。2.在鸟取县最东端的奥吉纳森山附近新发现了一种形态非常不同的蒙古乳杆菌小种，命名为Ohgiosen小种。3.对鸟取县及邻近地区蒙古乳杆菌种群的11个形态性状进行主成分分析，发现有3个种群与地理位置有较好的对应关系。4.采集了曲柄藻类11个种中的6个种的DNA样本。一项系统发育分析刚刚开始。5.解释四倍体兼性球藻雌雄异体出现率极高的模型。

The Leiobunum curvipalpe-group, consisting of 11 species (L.hiraiwai, L.montanum, L.kohyai, L.sadoense, L.simplum, L.hiasai, L.hikocola, L.curvipalpe, L.tohokuense, L.globosum, and L.manubriatum) shows great karyotypic variability both between and within species. Moreover, in two species of the group.occurrence of polyploid races are also known. Geographical patterns of the karyotypic differentiation and the role of the chromosomal hybrid zones in the speciation process of the group were investigated. The principal results obtained are as follows. 1.It was found that chromosomes of Leiobunum mohtanum varied from 2n=18 to 20/22 in eastern part of the Chugoku Mountains, Honshu. 2.A morphologically very divergent form of L.montanum, named Ohginosen race, was newly found around Mt Ohginosen in easternmost Tottori Prefecture. 3.Principal component analyses of 11 morphological characters for populations of L.montanum in and near Tottori Prefecture revealed occurrence of three groups that correspond well with geographical locations. 4.Samples for DNA analyses were accumulated for six of 11 species of the curvipalpe-group. A phylogenetic analysis is just getting underway. 5.A model to explain extraordinarily high emergence of gynandromorphs in a tetraploid facultative thelytoke, L.globosum.