Data from: Studies in Lichens and Lichenicolous Fungi – no. 18: resolution of three names introduced by Degelius and Magnusson based on material from the Great Smoky Mountains

Arthonia biseptata is shown to be a species of Mycoporum, likely narrowly endemic to high elevations of the southern Appalachian Mountains and the new combination M. biseptatum is proposed. Lecidea degelii is shown to apply to the sorediate morphotype of Porpidia albocaerulescens. The results of molecular phylogenetic analyses of nrITS and mtSSU sequence data of sorediate and esorediate populations of P. albocaerulescens are presented. These analyses recovered the sorediate and esorediate morophotypes together in a single clade as strongly-supported monophyletic entities. As a result the new combination Porpidia degelii is proposed, the species illustrated, and the North American distribution of P. degelii with respect to P. albocaerulescens is discussed. These data strongly refute the notion that “species pairs” do not exist in Porpidia. Lecidea subtilis is placed in synonymy with Pyrrhospora varians.

研究证实双隔节裂衣（Arthonia biseptata）隶属于霉蜡盘衣属（Mycoporum），该物种极可能仅狭域分布于阿巴拉契亚山脉南部的高海拔区域，同时本文提出该物种的新组合态M. biseptatum。研究表明，原鉴定为德格尔盘衣（Lecidea degelii）的类群实为白斑岩脐衣（Porpidia albocaerulescens）的粉芽形态型。本文报道了白斑岩脐衣粉芽型与非粉芽型种群的核糖体内部转录间隔区（nrITS）及线粒体小亚基核糖体RNA基因（mtSSU）序列的分子系统发育分析结果。该系统发育分析将两类形态型聚为同一演化支，形成支持度极高的单系类群。据此正式提出新组合德格尔岩脐衣（Porpidia degelii），并对该物种进行了形态图示，同时讨论了德格尔岩脐衣在北美的分布格局及其与白斑岩脐衣的分布关联。上述研究结果有力驳斥了“岩脐衣属（Porpidia）中不存在‘物种对’”这一学术观点。将细瘦盘衣（Lecidea subtilis）处理为变紫黄蜡衣（Pyrrhospora varians）的同物异名。