Fuscopannaria leucosticta is a rare lichen that exhibits an apparent specificity for old wet forests in eastern Canada, and may, consequently, be sensitive to anthropogenic disturbance. Estimates of the current distribution and population size are highly uncertain. Effective conservation planning requires improving our understanding of both its current distribution and the factors that influence habitat suitability. We built a MaxEnt distribution model with interpolated climate data, depth to water table mapping, forest inventory data, and herbarium collection data for F. leucosticta in New Brunswick, Canada. We tested model performance via field verifications in high-probability areas with no record of previous surveys. We found F. leucosticta in 13 out of 22 previously unsurveyed locations with a predicted high probability of occurrence. Selected variables included the presence of cedar in the canopy and a lack of recent anthropogenic disturbance, as well as mean annual rainfall and degree days above 0°C. These associations are likely a result of the lichen’s low reproductive output and the thermal and hydration requirements of its cyanobacterial photobiont. Our study affirms several previous claims about habitat associations of the species, and provides focus for conservation efforts in the future.

Fuscopannaria leucosticta是一种稀有的地衣，对加拿大东部的古老湿林表现出明显的特异性，因此可能对人为干扰敏感。当前分布和人口规模的估计高度不确定。有效的保护规划要求我们加深对其当前分布以及影响栖息地适宜性的因素的了解。我们建立了与插值气候数据，深度防水表的映射，森林资源清查数据和标本馆收集数据的最大墒分布模型F. leucosticta在加拿大新不伦瑞克。我们通过高概率区域中的现场验证测试了模型性能，没有以前的调查记录。我们发现了白念珠菌在22个先前未进行调查的位置中，有13个发生了预测的高发生概率。选定的变量包括：树冠中存在雪松和缺乏近期的人为干扰，以及年平均降雨量和高于0°C的气温天数。这些联系可能是由于地衣的低繁殖产量以及其蓝细菌光生物素的热和水合作用所致。我们的研究肯定了先前关于该物种的栖息地关联的一些主张，并为将来的保护工作提供了重点。