Data from: The phylogenetic significance of fruit anatomical and micromorphological structures in Chinese Heracleum and related taxa (Apiaceae)

Fruit anatomical and micromorphological structures from 28 species of Heracleum and three species of Angelica as outgroups were examined under light microscopy to identify characters useful in delimiting clades circumscribed in a previous molecular phylogenetic study. Maximum parsimony analyses of 20 fruit structural characters resulted in a generally poorly resolved strict consensus tree, yet one whose major clades matched those revealed previously. Angelica apaensis and Heracleum xiaojinense are best treated as the single species Angelica apaensis within Angelica s. s. All remaining Heracleum species share a highly lignified hypendocarp and a lignified endocarp, vascular bundles in marginal wings situated in the middle of the wing, and a commissure width the same as the mericarp width. These Heracleum species are recognized in four major clades with the following fruit structural features: (1) Heracleum s. s., having non-septate, clavate dorsal vittae that do not extend to the bottom of the seed; (2) Candicans (Villosa) clade, having marginal wings approximately half the width of the fruit and small seeds; (3) Millefolia clade, having narrow marginal wings, long dorsal vittae, large seeds, and rib oil ducts; and (4) Tetrataenium s. s., having prominent dorsal ribs, very wide marginal wings, dorsal and commissural vittae of similar length, 3‐4 commissural vittae, and very small seeds.

本研究借助光学显微镜（light microscopy），对28种独活属（Heracleum）植物及3种作为外类群（outgroups）的当归属（Angelica）植物的果实解剖结构与微观形态特征进行观察，旨在筛选可用于界定此前分子系统发育研究中划定的演化支（clades）的形态性状。对20项果实结构性状开展的最大简约法（Maximum Parsimony）分析得到的严格合意树整体分辨率较低，但其中的主要演化支与此前研究揭示的结果基本吻合。当归apaensis（Angelica apaensis）与小金独活（Heracleum xiaojinense）最适宜处理为狭义当归属（Angelica s. s.）下的单一物种当归apaensis。其余所有独活属物种均具备以下共同特征：高度木质化的下果皮（hypendocarp）与木质化的内果皮（endocarp），边缘翅内的维管束位于翅的中部，结合面宽度与分果瓣（mericarp）宽度一致。这些独活属物种可划分为4个主要演化支，各自对应以下果实结构特征：（1）狭义独活属（Heracleum s. s.）：具无分隔的棒状背油管（dorsal vittae），且油管未延伸至种子底部；（2）Candicans (Villosa)支系：边缘翅宽度约为果实的一半，种子体积较小；（3）Millefolia支系：边缘翅狭窄，背油管较长，种子较大，且具肋油管；（4）狭义四带芹属（Tetrataenium s. s.）：背棱显著，边缘翅极宽，背油管与结合面油管（commissural vittae）长度相近，具3~4条结合面油管，种子体积极小。