As parasites depend on their hosts and play a significant role in their ecology and evolution, we hypothesized an association between the host dispersal capacity and the intraspecific variability of their host-specific parasites. We investigated the morphological variability of the gill monogeneans Cichlidogyrus gistelincki and C. milangelnari parasitizing the Tanganyika cichlids ‘Ctenochromis’ horei and Cyprichromis microlepidotus, respectively. The profound ecological and behavioural differences between these host species allowed us to assume that the former is a good and the latter a poor disperser. Specimens of monogeneans were collected from cichlids inhabiting different locations at the northern end of Lake Tanganyika. Sequences of the 28S rDNA gene were used to confirm parasite conspecificity. Dorsal and ventral anchors of the attachment organ of parasite specimens were used to evaluate variability in shape. Geomorphometric analyses revealed that populations of C. milangelnari, which parasitize poorly dispersing cichlids, are more differentiated than populations of C. gistelincki infecting well-dispersing hosts. Both anchors showed significant shape variation between populations of C. milangelnari. In C. gistelincki, anchors were highly similar in comparisons of populations from nearby and from distant locations.

中文翻译：

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寄生在坦噶尼喀湖中表现出不同传播能力的两种慈鲷寄主的慈鲷 (Monogenea) 的种内形态变异

由于寄生虫依赖于宿主并在其生态和进化中发挥重要作用，我们假设宿主传播能力与其宿主特异性寄生虫的种内变异性之间存在关联。我们研究了分别寄生于坦噶尼喀慈鲷 'Ctenochromis' horei 和 Cyprichromis microlepidotus 的鳃单系 Cichlidogyrus gistelincki 和 C. milangelnari 的形态变异性。这些宿主物种之间深刻的生态和行为差异使我们能够假设前者是一种好的传播者，而后者是一种较差的传播者。从栖息在坦噶尼喀湖北端不同地点的慈鲷收集了单殖吸虫的标本。28S rDNA 基因的序列用于确认寄生虫的同种性。寄生虫标本附着器官的背侧和腹侧锚用于评估形状的可变性。地貌测量分析表明，寄生于分散性较差的慈鲷的 C. milangelnari 种群比感染分散性良好的宿主的 C. gistelincki 种群分化程度更高。两个锚点在 C. milangelnari 种群之间显示出显着的形状变化。在 C. gistelincki 中，在比较来自附近和远处地点的种群时，锚点非常相似。两个锚点在 C. milangelnari 种群之间显示出显着的形状变化。在 C. gistelincki 中，在比较来自附近和远处地点的种群时，锚点非常相似。两个锚点在 C. milangelnari 种群之间显示出显着的形状变化。在 C. gistelincki 中，在比较来自附近和远处地点的种群时，锚点非常相似。