Avena breviaristata, collected only once (1882) in Algeria and never re‐collected since, is a very mysterious grass species because unfortunately even the type specimen got lost 60–80 years ago. Morphological information on this species was thus based on a few published descriptions, which made it difficult, however, to correctly infer the genus affiliation of this morphologically odd species. Avena breviaristata became affiliated in the past with various oat‐like genera (Avenula, Helictotrichon, Tricholemma). Due to the recent rediscovery of the type specimen at the P herbarium and the opportunity to study this specimen, we report here on the morphological characters of A. breviaristata, underpinned by meaningful illustrations. They are discussed in comparison with the morphology of representative species of the above‐mentioned genera. Uncommon characters of the spikelets (type of disarticulation of the rachilla, lemma structure, lodicules) and to some extent of the inflorescences, leaves and leaf sheaths support the inclusion of A. breviaristata in the North African genus Tricholemma. Considering biogeography, T. breviaristatum from the arid Hauts Plateaux in Algeria is a highly xeromorphic counterpart of the mesomorphic species T. jahandiezii, which is confined to higher altitudes of the rather humid Moyen Atlas in Morocco. This underlines the status of Tricholemma as a relic endemic. Our morphological survey supports the classification of Avenula (only A. pubescens) as separate from Helictotrichon s.str. and Helictochloa. Moreover, morphological evidence does not support an origin of A. pubescens by intergeneric hybridization between the latter genera as hypothesized in some prior studies. Especially the glabrous palea, the special shape of the lodicules and the structure of the awn show no intermediacy. The complicated history of the type collection of T. breviaristatum and the role of botanical authors are given.

中文翻译：

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恢复仅收集一次（1882年）的阿尔及利亚特有草种Avena breviaristata的类型标本：形态，分类学和植物学历史

Avena breviaristata是一种非常神秘的草种，在阿尔及利亚仅收集过一次（1882），此后再也没有再收集过，因为不幸的是，这种标本甚至在60-80年前就丢失了。因此，有关该物种的形态学信息是基于一些已发表的描述，但是，很难正确地推断这种形态奇特的物种的属属。过去，Avena breviaristata隶属于各种燕麦样属（Avenula，Helictotrichon，Tricholemma）。由于最近在植物标本室发现了该类型标本，并且有机会研究该标本，因此我们在此报告了短。草的形态特征。，以有意义的插图为基础。将它们与上述属的代表性物种的形态进行比较。小穗的生僻字符（小穗轴截断术的类型，引理结构，浆片）和花序，叶和叶鞘一定程度上支撑列入A. breviaristata北非属Tricholemma。考虑到生物地理学，来自阿尔及利亚干旱Hauts Plateaux的T. breviaristatum是同种亚种T. jahandiezii的高度干态对应物，而T. jahandiezii被限制在摩洛哥相当潮湿的Moyen Atlas的较高海拔。这突出了口蘑的地位作为文物特有的。我们的形态学调查支持将Avenula（仅A. pubescens）与Helictotrichon s.str。分开进行分类。和Helictochloa。此外，形态学证据不支持通过在先前的一些研究中所假设的后种之间的种间杂交来支持毛发曲霉的起源。特别是无毛的内脏，the的特殊形状和遮阳篷的结构没有中介作用。给出了T. breviaristatum类型收藏的复杂历史以及植物学家的作用。