Molecular analyses reveal semi-cryptic species in Xanthoparmelia tasmanica

Evolutionary relationships between the major populations of Xanthoparmelia tasmanica are investigated using parsimony, likelihood, and Bayesian analyses of ITS sequence data. Results indicate that this taxon is comprised of at least two geographically distinct lineages. Moreover, these lineages belong to two larger clades of Xanthoparmelia s. str. (also defined by geography) that were recognized in previous phylogenetic studies of the genus. The geographically distinct, but morphologically and chemically identical populations of X. tasmanica are treated here as separate taxa with independent evolutionary histories. While the name X. tasmanica is properly applied to Australasian populations, populations from North America that were previously called X. tasmanica are here referred to X. hypofusca.本研究借助ITS序列数据的简约法、最大似然法与贝叶斯分析，对塔斯曼尼亚黄髓梅（Xanthoparmelia tasmanica）主要种群间的演化关系展开探究。研究结果表明，该分类群至少包含两个地理分化的演化谱系。此外，这两个谱系隶属于狭义黄髓梅属（Xanthoparmelia s. str.）的两个更大演化支，该属的先前系统发育研究已基于地理特征界定了这两个演化支。本研究将地理上分化但形态与化学特征完全一致的塔斯曼尼亚黄髓梅种群，视作具有独立演化历史的独立分类群。尽管塔斯曼尼亚黄髓梅的学名仅适用于澳大拉西亚种群，但此前被命名为塔斯曼尼亚黄髓梅的北美种群，现被归入淡褐黄髓梅（Xanthoparmelia hypofusca）。