Abstract Erioderma pedicellatum, an enigmatic boreal cyanolichen epiphyte is sympatric with the widespread pantropical cyanolichen Coccocarpia palmicola in cool and damp forests in Atlantic parts of Canada. After sampling co-occurring specimens of these lichens in Newfoundland, we quantified important hydration traits. We hypothesized that 1: these lichens restricted to wet forests have higher internal water holding capacity (WHCinternal) than what humid air and dewfall can provide, and 2: the rare E. pedicellatum has higher WHCinternal and / or WHCtotal than the widespread C. palmicola. Both hypotheses were supported: Mean WHCinternal across a wide thallus size range was 0.26 and 0.35 mm H2O in C. palmicola and E. pedicellatum, respectively; corresponding mean WHCtotal were 0.73 and 0.86 mm. These high WHC-levels could only be filled by liquid hydration sources. Because WHC strongly increased with thallus size, larger specimens needed even more water (1.7 mm), emphasizing these species’ dependency on rain and thus wet forests.

中文翻译：

---

蓝藻 Erioderma pedicellatum 和 Coccocarpia palmicola 需要的不仅仅是露水来填充它们的蓄水能力

摘要 Erioderma pedicellatum 是一种神秘的北方蓝藻附生植物，与加拿大大西洋地区凉爽潮湿的森林中广泛分布的泛热带蓝藻 Coccocarpia palmicola 同域。在纽芬兰对这些地衣的共生标本进行采样后，我们量化了重要的水合作用特征。我们假设 1：这些仅限于潮湿森林的地衣具有比潮湿空气和露水所能提供的更高的内部持水能力 (WHCinternal)，以及 2：稀有的 E. pedicellatum 具有比广泛分布的 C. palmicola 更高的 WHCinternal 和/或 WHCtotal . 两个假设都得到支持：在 C. palmicola 和 E. pedicellatum 中，在广泛的叶绿体大小范围内的平均 WHCinternal 分别为 0.26 和 0.35 mm H2O；相应的平均 WHCtotal 分别为 0.73 和 0.86 毫米。这些高 WHC 水平只能由液体水合源填充。由于 WHC 随菌体大小而显着增加，因此较大的标本需要更多的水（1.7 毫米），这强调了这些物种对雨水和潮湿森林的依赖。