Data from: Integrated molecular and morphological studies of the Daucus guttatus complex (Apiaceae)

In a previous study using 94 nuclear orthologs, we reported the species status of the Daucus guttatus complex to be unresolved, partitioned into three clades. In the present study, a subset of ten of these 94 orthologs was used to infer the phylogeny of the D. guttatus complex and related species. A near parallel set of accessions, planted in a common garden, was used for morphological analyses. The molecular trees are highly resolved for most of the clades, grouping accessions of the D. guttatus complex into four clades. Bayesian concordance analysis and a coalescent approach gave slightly different topologies. Morphological data likewise support four taxa in the complex. Moreover, herbarium research from a companion study informs nomenclature for taxa of the complex. We identify these four clades as D. bicolor, D. conchitae, D. guttatus, and D. setulosus; internested in or among these segregates are the phenetically distinctive species D. glochidiatus, D. involucratus, D. littoralis, and D. pusillus. Our research redefines species variation in the D. guttatus complex, clarifies species names, interspecific relationships, confirms a useful subset of nuclear orthologs for studies of dominant topologies of Daucus, and discovers morphological characters allowing proper identification of the four species of the D. guttatus complex and related species.

此前一项基于94个核直系同源基因（nuclear orthologs）的研究中，我们曾指出斑点胡萝卜复合群（Daucus guttatus complex）的物种界定尚未明确，该类群被划分为三个演化支（clade）。本研究选取其中10个核直系同源基因构成子集，用于推断斑点胡萝卜复合群及其近缘物种的系统发育（phylogeny）关系。我们选取一组近乎平行的种质材料（accession），于共同花园（common garden）中栽培后开展形态学分析。分子系统树对多数演化支的解析度极高，将斑点胡萝卜复合群的种质材料划分为四个演化支。贝叶斯一致性分析（Bayesian concordance analysis）与溯祖分析法（coalescent approach）得到的系统发育拓扑结构（topology）略有差异。形态学数据同样支持该复合群内存在4个分类单元（taxon）。此外，一项配套研究中的标本馆（herbarium）研究结果，可为该复合群内分类单元的命名（nomenclature）提供参考依据。我们将这四个演化支分别界定为D. bicolor、D. conchitae、D. guttatus与D. setulosus；表型特征显著的D. glochidiatus、D. involucratus、D. littoralis及D. pusillus，则嵌套或分布于这些分离类群之间。本研究重新界定了斑点胡萝卜复合群内的物种变异范围，厘清了物种名称与种间关系，验证了一套可用于胡萝卜属（Daucus）物种系统发育优势拓扑结构研究的核直系同源基因子集，同时发现了可用于准确鉴定该复合群4个物种及其近缘物种的形态学特征。