Data from: Character evolution and missing (morphological) data across Asteridae

Premise of the study: Our current understanding of flowering plant phylogeny provides an excellent framework for exploring various aspects of character evolution through comparative analyses. However, attempts to synthesize this phylogenetic framework with extensive morphological datasets have been surprisingly rare. Here, we explore character evolution in Asteridae (asterids), a major angiosperm clade, using an extensive morphological data set and a well-resolved phylogeny. Methods: We scored 15 phenotypic characters (spanning chemistry, vegetative anatomy, and floral, fruit, and seed features) across 248 species for ancestral state reconstruction using a phylogenetic framework based on 73 plastid genes and the same 248 species. Key results: Iridoid production, unitegmic ovules, and cellular endosperm were all reconstructed as synapomorphic for Asteridae. Sympetaly, long associated with asterids, shows complex patterns of evolution, suggesting it arose several times independently within the clade. Stamens equal in number to the petals is likely a synapomorphy for Gentianidae, a major asterid subclade. Members of Lamianae, a major gentianid subclade, are potentially diagnosed by adnate stamens, unilacunar nodes, and simple perforation plates. Conclusions: The analyses presented here provide a greatly improved understanding of character evolution across Asteridae, highlighting multiple characters potentially synapomorphic for major clades. However, several important parts of the asterid tree are poorly known for several key phenotypic features (e.g., degree of petal fusion, integument number, nucellus type, endosperm type, iridoid production). Further morphological, anatomical, developmental, and chemical investigations of these poorly known asterids are critical for a more detailed understanding of early asterid evolution.研究背景：当前学界对被子植物系统发育的认知，为通过比较分析探索性状演化的多个维度提供了极佳的研究框架。然而，将该系统发育框架与大规模形态学数据集进行整合的相关尝试却相对少见。本研究依托大规模形态学数据集与高分辨率系统发育树，对菊亚纲（Asteridae）——一个主要的被子植物支系——内的性状演化展开探究。 研究方法：我们针对248个物种的15个表型性状（涵盖化学特征、营养解剖学特征以及花、果实和种子性状）进行编码，基于包含73个质体基因且对应相同248个物种的系统发育框架开展祖先状态重建（ancestral state reconstruction）分析。 主要结果：环烯醚萜合成、单珠被胚珠以及细胞型胚乳均被重建为菊亚纲的共衍征。长期以来与菊亚纲相关联的合瓣花（sympetaly）呈现出复杂的演化模式，表明其在该支系内曾多次独立起源。雄蕊与花瓣数目相等这一特征，大概率是龙胆亚纲（Gentianidae，菊亚纲的一个主要亚支系）的共衍征。唇形亚纲（Lamianae，龙胆亚纲的一个主要亚支系）的类群，或许可通过贴生雄蕊、单隙节以及单穿孔板作为鉴别特征。 研究结论：本研究的分析结果极大提升了我们对菊亚纲内性状演化的认知，揭示了多个可作为主要支系共衍征的潜在性状。不过，菊亚纲系统树的多个关键分支的若干核心表型性状仍所知有限，例如花瓣融合程度、珠被数目、珠心类型、胚乳类型以及环烯醚萜合成情况。针对这些研究尚不充分的菊亚纲类群，开展进一步的形态学、解剖学、发育生物学及化学研究，对于更深入地阐明菊亚纲的早期演化历程至关重要。