Goldman M A, LoVerde P T, Chrisman C L
Can J Genet Cytol. 1980;22(3):361-7. doi: 10.1139/g80-044.
Species of the subgenus Bulinus s.s. occur in a polyploid series which is of interest because of the rarity of polyploidy in animal species and because there appears to be a relation between ploidy level and ability to transmit Schistosoma haematobium, a parasite of major public health importance. We describe a technique for the preparation of standard karyotypes using cell suspensions from colchicine-treated embryos. The results for two diploid species, B. tropicus (Krauss) and B. natalensis (Küster), are presented. Both karyotypes consist of 15 metacentric and 3 submetacentric chromosomes. However, differences in centromere position are found in four pairs of chromosomes, and in the appearance of a secondary constriction. Because B. natalensis may represent a relict taxon involved in the origin of the polyploids, the results of significance for future work on the phylogeny of this group.
泡螺亚属（狭义）的物种以多倍体系列存在，这因其在动物物种中多倍体现象罕见而备受关注，还因为倍性水平与传播埃及血吸虫（一种具有重大公共卫生重要性的寄生虫）的能力之间似乎存在关联。我们描述了一种使用秋水仙碱处理过的胚胎的细胞悬液制备标准核型的技术。文中给出了两种二倍体物种——热带泡螺（克劳斯）和纳塔尔泡螺（屈斯特）的结果。两种核型均由15条中着丝粒染色体和3条亚中着丝粒染色体组成。然而，在四对染色体的着丝粒位置以及一个次缢痕的外观上发现了差异。由于纳塔尔泡螺可能代表了参与多倍体起源的一个残遗分类群，这些结果对该类群系统发育的未来研究具有重要意义。
