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.

本研究通过光学显微镜（light microscopy）观察了28种独活属（Heracleum）植物与3种作为外类群（outgroups）的当归属（Angelica）植物的果实解剖结构及微观形态特征，旨在筛选出可用于界定此前分子系统发育研究中划定的演化支（clades）的有效性状。对20项果实结构性状开展的最大简约法（maximum parsimony）分析得到的严格一致性树（strict consensus tree）整体分辨率较低，但其主要演化支与此前研究揭示的演化支基本吻合。阿坝当归（Angelica apaensis）与小金独活（Heracleum xiaojinense）最适宜被归为狭义当归属（Angelica s. s.）下的单一物种阿坝当归（Angelica apaensis）。其余所有独活属物种均具有以下共同特征：高度木质化的下果皮（hypendocarp）与内果皮（endocarp）、位于边缘翅（marginal wings）中部的维管束，以及合生面（commissure）宽度与分果瓣（mericarp）宽度相等。该类独活属植物可划分为4个主要演化支，各演化支对应的果实结构特征如下：(1) 狭义独活属（Heracleum s. s.）：具无隔膜的（non-septate）、棍棒状的（clavate）背油管（dorsal vittae），且油管未延伸至种子底部；(2) 白花独活（Candicans (Villosa)）演化支：边缘翅宽度约为果实宽度的一半，且种子体积较小；(3) 多叶独活（Millefolia）演化支：边缘翅狭窄、背油管较长、种子体积较大且具肋油管（rib oil ducts）；(4) 狭义四带芹属（Tetrataenium s. s.）：具显著的背棱、极宽的边缘翅，背油管与合生面油管长度相近，具3~4条合生面油管，且种子体积极小。