Kvist Sebastian, Earl Ismay, Kink Ester, Oceguera-Figueroa Alejandro, Trontelj Peter
Department of Natural History, Royal Ontario Museum, 100 Queen's Park, Toronto, ON M5S 2C6, Canada; Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, ON M5S 2B4, Canada.
Department of Natural History, Royal Ontario Museum, 100 Queen's Park, Toronto, ON M5S 2C6, Canada; Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, ON M5S 2B4, Canada.
Mol Phylogenet Evol. 2023 Jan;178:107648. doi: 10.1016/j.ympev.2022.107648. Epub 2022 Oct 23.
The Holarctic leech genus Haemopis currently includes 11 species, all of which are macrophagous, as opposed to their more infamous bloodfeeding counterparts among hirudiniform leeches. In spite of their ecological importance as fish food and predators of freshwater invertebrates, there is a paucity of data regarding morphology and genetic variation that might guide future identification efforts for members of the genus. The lack of detailed descriptions of distinguishing morphological features, coupled with the absence of a robust phylogenetic hypothesis for the genus, have conspired to prevent meaningful inferences on the natural history of the group. In an attempt to remedy this, we present new genetic (using COI, 12S rDNA, 28S rDNA and 18S rDNA) data for the majority of the known species diversity within the genus in order to both infer a phylogenetic hypothesis and to introduce authoritative DNA barcodes for the newly collected species. The potential of these barcodes is increased through rigorous morphological investigations of the specimens, with comparisons to the original literature. Our resulting phylogenetic hypothesis is agnostic as to the geographic origin of the genus, with equal probability afforded to both a Nearctic and Palearctic origin. Beyond this, we show that there is a strong tendency towards a barcoding gap within the genus, but that a distinct gap is lacking due to the relatively high genetic variation found within H. marmorata. Taken together, our results shed light on species delimitation within, and evolutionary history of, this often-neglected group of leeches.
全北区的水蛭属血红蛭目前包含11个物种，它们均为食大型生物者，这与它们在蛭形水蛭中更为臭名昭著的吸血同类不同。尽管它们作为鱼类食物以及淡水无脊椎动物的捕食者具有生态重要性，但关于形态学和遗传变异的数据却很匮乏，而这些数据可能会指导该属成员未来的鉴定工作。缺乏对显著形态特征的详细描述，再加上该属缺乏一个可靠的系统发育假说，共同导致无法对该类群的自然历史进行有意义的推断。为了弥补这一点，我们提供了该属内大多数已知物种多样性的新遗传数据（使用细胞色素氧化酶亚基I、12S核糖体DNA、28S核糖体DNA和18S核糖体DNA），以便既能推断出一个系统发育假说，又能为新采集的物种引入权威的DNA条形码。通过对标本进行严格的形态学研究，并与原始文献进行比较，这些条形码的潜力得以提升。我们得出的系统发育假说对该属的地理起源并不明确，北极起源和古北起源的可能性相同。除此之外，我们表明该属内存在条形码间隔的强烈趋势，但由于在斑纹血红蛭中发现相对较高的遗传变异，因此缺乏明显的间隔。综合来看，我们的结果为这一常被忽视的水蛭类群的物种界定及其进化历史提供了线索。
