Data from: A new perspective on Punctelia subrudecta (Parmeliaceae) in North America: previously rejected morphological characters corroborate molecular phylogenetic evidence and provide insight into an old problem

In North America the names Punctelia subrudecta and P. perreticulata have variously been applied to corticolous sorediate Punctelia specimens with lecanoric acid and a pale lower surface. ITS1, 5.8S, and ITS2 sequence data were generated from a geographically and morphologically broad sampling from within these specimens, and a molecular phylogeny was inferred. A combined approach using morphology, geography, and phylogeny was used to circumscribe three distinct species in North America, one of which is described as new to science (P. caseana), one of which is finally confirmed for the continent (P. jeckeri), and one whose original circumscription is validated (P. perreticulata). The phylogeny inferred from ITS sequence data supports the taxonomic value of the following morphological characters for distinguishing species in this group: presence/absence of pruina; conidium type and length (although see discussion of P. jeckeri), and presence/absence of scrobiculae on the upper surface. A key to the North American species of Punctelia is provided.

在北美地区，Punctelia subrudecta与P. perreticulata两个分类名称曾被不同地应用于树皮生（corticolous）、具粉芽（sorediate）且含有扁枝衣酸（lecanoric acid）、下表面色泽较浅的点梅属（Punctelia）标本。研究者对该类标本进行了覆盖广泛地理范围与形态多样性的采样，并生成了其ITS1、5.8S rRNA基因及ITS2的序列数据，进而推断得到分子系统发育关系。本研究结合形态学、地理学与系统发育学的综合分析手段，对北美地区的该类点梅属物种进行了分类界定，共划分出3个独立物种：其一为科学新种（P. caseana），其二为该大陆首次正式确认的物种（P. jeckeri），其三则验证了其原始分类界定的合理性（P. perreticulata）。基于ITS序列数据推断得到的系统发育树支持以下形态学特征在该类群的物种区分中具备分类学价值：粉霜（pruina）的有无、分生孢子（conidium）的类型与长度（详见关于P. jeckeri的相关讨论），以及上表面是否存在穴点（scrobiculae）。本研究同时提供了北美地区点梅属物种的分类检索表。