MOE Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Science, Fudan University, Songhu Road 2005, Shanghai, China.
College of Science and Engineering, James Cook University, Townsville, Qld 4811, Australia.
Mol Phylogenet Evol. 2023 Apr;181:107725. doi: 10.1016/j.ympev.2023.107725. Epub 2023 Feb 1.
There is increasing interest in the diversity and phylogeography of aquatic invertebrate zooplankton in the Eastern Palearctic, yet this topic remains largely unexplored in China. Here, we investigated the lineage diversity and phylogeography of an important cladoceran taxon, the Scapholeberis kingii (Cladocera: Daphniidae) species complex, members of which live in the surface layers of freshwater ecosystems. We identified only the S. smirnovi morphospecies from this species complex in 29 of 491 Chinese water bodies examined. Its phylogenetic position was verified using both a mitochondrial (mitochondrial cytochrome c oxidase subunit I; COI) and a nuclear marker (the nuclear large subunit ribosomal RNA gene; 28S). Pronounced geographical separation among three S. smirnovi mitochondrial lineages was observed in China: only a single lineage (Lineage A) was present in the Eastern Plain, whereas Lineages B and C were restricted to the Inner Mongolia-Xinjiang Plateau and the Qinghai-Tibetan Plateau respectively. This deep mtDNA divergence and the substantial genetic differentiation among S. smirnovi populations from different regions is likely a result of the rapid uplift of the Qinghai-Tibetan Plateau and associated ecological changes. This study contributes to an understanding of the genetic diversity of the S. kingii complex, a key component of neustonic zooplankton.
人们对东古北界水生无脊椎动物浮游动物的多样性和系统地理学越来越感兴趣，但在中国，这个主题在很大程度上仍未得到探索。在这里，我们研究了一个重要的枝角类分类群，即 S. kingii（枝角目：Daphniidae）物种复合体的系统发育多样性和系统地理学，其成员生活在淡水生态系统的表层。在检查的 491 个中国水体中，我们仅从该物种复合体中识别出了 S. smirnovi 形态种。通过使用线粒体（线粒体细胞色素 c 氧化酶亚基 I；COI）和核标记（核大亚基核糖体 RNA 基因；28S）验证了其系统发育位置。在中国观察到三个 S. smirnovi 线粒体谱系之间存在明显的地理分离：仅存在于东部平原的单个谱系（谱系 A），而谱系 B 和 C 分别局限于内蒙古-新疆高原和青藏高原。这种深远的 mtDNA 分化以及来自不同地区的 S. smirnovi 种群之间的大量遗传分化可能是青藏高原快速隆起和相关生态变化的结果。本研究有助于了解 S. kingii 复合体的遗传多样性，该复合体是海洋浮游动物的关键组成部分。
