The global decline in biodiversity has invigorated the field of conservation biology, leading to investigation of species at risk of extinction in hopes of generating effective conservation strategies. Some highly diverse taxa, such as lichens, have received considerably less conservation attention, compared to plants and vertebrates. Here we add present the results of a comprehensive demographic survey and IUCN risk assessment of Cladonia submitis, a conspicuous macrolichen endemic to the Mid-Atlantic coast of eastern North America, across the core of its range. While it was found at several new locations, we found the species had disappeared from many locations where it once occurred. This decline, in conjunction with its restricted range, supports a status of Endangered under IUCN guidelines. While fire and sea level rise likely pose threats to the species, the most immediate threat is urbanization and alteration of coastal dunes. This evaluation does not consider collections from Japan and Sakhalin Island which have been assigned as C. submitis, due to differences in range, habitat and morphology that suggest this identification is inaccurate. In the absence of a proper taxonomic assessment or phylogenetic study to answer this question of identity, Japanese specimens could not be considered in this assessment. Altogether, this study provides a basis for effective management strategies of this charismatic species whose core range consists of the densely populated region between the American cities of Boston and Washington, D.C.

全球生物多样性的下降推动了保护生物学领域的发展，从而导致了对濒临灭绝物种的调查，以期提出有效的保护策略。与植物和脊椎动物相比，一些高度多样化的类群，例如地衣，受到的保护少得多。在这里，我们添加了目前的综合人口调查结果和IUCN乌头氏菌的IUCN风险评估，是北美东部中大西洋沿岸的一种明显的大型地衣，横跨其范围的核心。虽然在几个新位置发现了该物种，但我们发现该物种已从曾经发生过的许多位置消失了。这种下降及其有限的范围，支持了《自然保护联盟》指导下的濒危状况。尽管火灾和海平面上升可能对该物种构成威胁，但最直接的威胁是城市化和沿海沙丘的改变。该评估不考虑来自日本和萨哈林岛的已被指定为C. Submitis的藏品，由于范围，栖息地和形态的差异，表明此识别不正确。在没有适当的分类学评估或系统发育研究来回答这一身份问题的情况下，该评估不能考虑日本标本。总而言之，这项研究为这种具有超凡魅力的物种的有效管理策略提供了基础，该物种的核心范围包括美国波士顿和华盛顿特区之间的人口稠密地区