Taylor T N, Hass H, Kerp H, Krings M, Hanlin R T
Department of Ecology and Evolutionary Biology, and Natural History Museum and Biodiversity Research Center, University of Kansas, Lawrence 66045, USA.
Mycologia. 2005 Jan-Feb;97(1):269-85.
We describe a perithecial, pleomorphic ascomycetous fungus from the Early Devonian (400 mya) Rhynie chert; the fungus occurs in the cortex just beneath the epidermis of aerial stems and rhizomes of the vascular plant Asteroxylon. Perithecia are nearly spherical with a short, ostiolate neck that extends into a substomatal chamber of the host plant; periphyses line the inner surface of the ostiole. The ascocarp wall is multilayered and formed of septate hyphae; extending from the inner surface are elongate asci interspersed with delicate paraphyses. Asci appear to be unitunicate and contain up to 16 smooth, uniseriate-biseriate ascospores. The method of ascospore liberation is unknown; however, the tip of the ascus is characterized by a narrow, slightly elevated circular collar. Ascospores appear 1-5 celled, and germination is from one end of the spore. Also present along the stems and interspersed among the perithecia are acervuli of conidiophores that are interpreted as the anamorph of the fungus. Conidiogenesis is thallic, basipetal and probably of the holoarthric-type; arthrospores are cube-shaped. Some perithecia contain mycoparasites in the form of hyphae and thick-walled spores of various sizes. The structure and morphology of the fossil fungus is compared with modern ascomycetes that produce perithecial ascocarps, and characters that define the fungus are considered in the context of ascomycete phylogeny.
我们描述了一种来自早泥盆世（4亿年前）莱尼燧石层的具子囊壳的多形子囊菌；这种真菌存在于维管植物星木属气生茎和根状茎表皮下方的皮层中。子囊壳近球形，有一个短的、具孔口的颈部，延伸到寄主植物的气孔下腔；周丝排列在孔口内表面。子囊果壁是多层的，由具隔膜的菌丝构成；从内表面延伸出细长的子囊，其间散布着纤细的侧丝。子囊似乎是单囊壁的，含有多达16个光滑的、单列 - 双列的子囊孢子。子囊孢子的释放方式未知；然而，子囊顶端的特征是有一个狭窄的、略微隆起的圆形环。子囊孢子看起来有1 - 5个细胞，从孢子的一端萌发。沿着茎也存在并散布在子囊壳之间的是分生孢子梗的分生孢子盘，被解释为该真菌的无性型。分生孢子形成是体生的、向基式的，可能是全节孢子型；节孢子呈立方体状。一些子囊壳含有以各种大小的菌丝和厚壁孢子形式存在的菌寄生体。将这种化石真菌的结构和形态与产生具子囊壳子囊果的现代子囊菌进行了比较，并在子囊菌系统发育的背景下考虑了定义该真菌的特征。
