Epigeous and Hypogeous Pezizales of Western North America

真假羊肚菌和相关的杯状真菌（通常在地上形成产孢子的结构）以及松露（在地下产生孢子）都是子囊菌纲真菌。它们在进化上仅与担子菌纲的担子菌目的真正蘑菇有远亲关系。真正的羊肚菌和松露是最受追捧、最昂贵的可食用野生“蘑菇”。俄勒冈州立大学的南希·韦伯（Nancy Weber）博士和她的同事们正在研究这类真菌在美国西部的形态变化模式和地理分布，这一地区是这类真菌高度多样化的地区。对新收集的标本的研究将补充对博物馆保存的标本的研究，以便确定物种界限并描述可靠的形态特征以进行鉴定。目前还没有对北美这一重要真菌群的综合分类处理。除了作为美食的重要性之外，Pezizales目的成员在森林生态系统中发挥着关键作用。有些是松鼠、鹿和其他动物的重要食物。有些是森林树木的菌根共生体。在缺乏适当菌根真菌的情况下，树木吸收土壤养分的效率低下，很少能存活超过一年左右。一些Pezizales人是采砂者，回收森林碎片。有些是在火灾或其他干扰后第一批产生孢子的真菌。对西部森林生态动态的认识部分依赖于对这些森林树木菌根伴侣的准确鉴定，而这一基础的分类研究将有助于实现这一目标。

True and false morels and allied cup-fungi, which generally form spore-producing structures aboveground, and truffles, which sporulate belowground, are Ascomycete fungi placed in the class Pezizales. They are only distantly related evolutionarily to true mushrooms of the order Agaricales, class Basidiomycetes. True morels and truffles are among the most avidly sought, and expensive, edible wild "mushrooms." Dr. Nancy Weber and her colleagues at Oregon State University are studying the patterns of morphological variation and geographical distribution in this group of fungi throughout the western United States, an area of high diversity in the group. Studies of freshly collected specimens will complement studies of museum-preserved samples, in order to determine species circumscriptions and describe reliable morphological features for identification. At present there is no comprehensive taxonomic treatment of this important group of fungi for North America. In addition to their importance as gourmet foods, members of the order Pezizales play key roles in forest ecosystems. Some are important as food for squirrels, deer, and other animals. Some are mycorrhizal symbionts of forest trees. In the absence of appropriate mycorrhizal fungi, trees take up soil nutrients inefficiently and rarely survive for more than a year or so. Some Pezizales are saprobes, recycling forest debris. And some are among the first fungi to sporulate following a fire or other disturbance. Understanding of the ecological dynamics of western forests depends in part on accurate identification of these mycorrhizal partners of forest trees, to be facilitated by this basic taxonomic study.