Department of Life Sciences, The Natural History Museum, London SW7 5BD, United Kingdom, and Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3DS, United Kingdom.
Botanischer Garten und Botanisches Museum, Freie Universität Berlin, 14195 Berlin, Germany.
Microbiol Spectr. 2017 Jul;5(4). doi: 10.1128/microbiolspec.FUNK-0052-2016.
The question of how many species of there are has occasioned much speculation, with figures mostly posited from around half a million to 10 million, and in one extreme case even a sizable portion of the spectacular number of 1 trillion. Here we examine new evidence from various sources to derive an updated estimate of global fungal diversity. The rates and patterns in the description of new species from the 1750s show no sign of approaching an asymptote and even accelerated in the 2010s after the advent of molecular approaches to species delimitation. Species recognition studies of (semi-)cryptic species hidden in morpho-species complexes suggest a weighted average ratio of about an order of magnitude for the number of species recognized after and before such studies. New evidence also comes from extrapolations of plant:fungus ratios, with information now being generated from environmental sequence studies, including comparisons of molecular and fieldwork data from the same sites. We further draw attention to undescribed species awaiting discovery in biodiversity hot spots in the tropics, little-explored habitats (such as lichen-inhabiting fungi), and material in collections awaiting study. We conclude that the commonly cited estimate of 1.5 million species is conservative and that the actual range is properly estimated at 2.2 to 3.8 million. With 120,000 currently accepted species, it appears that at best just 8%, and in the worst case scenario just 3%, are named so far. Improved estimates hinge particularly on reliable statistical and phylogenetic approaches to analyze the rapidly increasing amount of environmental sequence data.
有多少种真菌一直是人们猜测的问题，推测的数字大多在 50 万到 1000 万之间，在一个极端的例子中，甚至有相当一部分达到了惊人的 10 万亿。在这里，我们从各种来源检查新的证据，以得出全球真菌多样性的最新估计。从 18 世纪 50 年代开始，新物种描述的速度和模式没有接近渐近线的迹象，甚至在分子物种界定方法出现后的 21 世纪 10 年代加速了。对隐藏在形态种复合体中的（半）隐种的物种识别研究表明，在进行这些研究之后和之前，识别出的物种数量的加权平均值比大约高出一个数量级。新的证据还来自于植物与真菌比例的推断，现在从环境序列研究中获得了信息，包括对来自同一地点的分子和实地数据的比较。我们还提请注意在热带生物多样性热点地区、探索较少的栖息地（如地衣真菌）以及有待研究的收藏材料中有待发现的未描述物种。我们得出的结论是，普遍引用的 150 万种的估计是保守的，实际范围恰当地估计在 220 万到 380 万之间。目前有 12 万种已被接受的物种，这意味着目前最多只有 8%，在最坏的情况下只有 3%的物种被命名。更可靠的估计尤其取决于可靠的统计和系统发育方法，以分析快速增加的环境序列数据。
