Gruenstaeudl Michael, Urtubey Estrella, Jansen Robert K, Samuel Rosabelle, Barfuss Michael H J, Stuessy Tod F
Department of Systematic and Evolutionary Botany, Faculty Center of Botany, University of Vienna, Vienna, Austria.
Mol Phylogenet Evol. 2009 Jun;51(3):572-87. doi: 10.1016/j.ympev.2009.01.023. Epub 2009 Mar 3.
Subfamily Barnadesioideae (Asteraceae) consists of nine genera and 91 species endemic to South America. They include annual and perennial herbs, arching shrubs and trees up to 30m tall. Presumed sister to all other Asteraceae, its intergeneric relationships are key to understanding the early evolution of the family. Results of the only molecular study on the subfamily conflict with relationships inferred from morphology. We investigate inter- and intrageneric relationships in Barnadesioideae with novel DNA sequence data and morphological characters using parsimony, likelihood and Bayesian inference. All results verify Barnadesioideae as monophyletic and sister to the rest of the family. A basal split within the subfamily is recognized, with Chuquiraga, Doniophyton and Duseniella in one clade, and Arnaldoa, Barnadesia, Dasyphyllum, Fulcaldea, Huarpea and possibly Schlechtendalia in another. The largest genus, Dasyphyllum, is revealed as biphyletic with the two clades separating along subgeneric and geographic lines. Schlechtendalia, suggested as the earliest diverging lineage of the subfamily by morphological studies and parsimony analyses, is found in a more derived position under model-based inference methods. Competing phylogenetic hypotheses, both previous and present, are evaluated using likelihood-based tests. Evolutionary trends within Barnadesioideae are inferred: hummingbird pollination has developed convergently at least three times. An early vicariance in the subfamily's distribution is revealed. X=9 is supported as the ancestral base chromosome number for both Barnadesioideae and the family as a whole.
巴纳德斯菊亚科（菊科）由9个属和91个物种组成，均为南美洲特有。它们包括一年生和多年生草本植物、拱形灌木以及高达30米的乔木。该亚科被认为是所有其他菊科植物的姐妹群，其属间关系是理解菊科早期进化的关键。关于该亚科的唯一一项分子研究结果与从形态学推断出的关系相冲突。我们使用简约法、似然法和贝叶斯推断法，利用新的DNA序列数据和形态特征来研究巴纳德斯菊亚科的属间和属内关系。所有结果均证实巴纳德斯菊亚科为单系群，且是菊科其他类群的姐妹群。在该亚科内部识别出一个基部类群分支，其中楚基拉加属、多尼奥菲顿属和杜塞尼埃拉属在一个分支中，而阿诺尔多阿属、巴纳德斯属、达西菲勒姆属、富尔卡尔德属、瓦尔皮亚属以及可能的黄瑞香属在另一个分支中。最大的属达西菲勒姆属被发现是二系的，两个分支沿着亚属和地理界限分开。形态学研究和简约分析表明黄瑞香属是该亚科最早分化的谱系，但在基于模型的推断方法中，它处于一个更进化的位置。使用基于似然性的检验对先前和当前相互竞争的系统发育假说进行评估。推断出巴纳德斯菊亚科的进化趋势：蜂鸟传粉至少独立进化了三次。揭示了该亚科分布中的早期隔离现象。支持x = 9作为巴纳德斯菊亚科以及整个菊科的祖先基本染色体数。
