Stray Studies in the Coronophorales (Pyrenomycetes) 4-8 - ASCOfrance

304 J. A. Nannfeldtand, in three of them, also on the ascocarps. These bristles are exactly alike in allspecies, and their monophyletical origin can hardly be questioned. Even if thespecies are not homogeneous as to "Quellkorper" and spore number I find itmotivated and preferable to treat them as a separate genusdistinct from the bristle-lessNitschkia.(Acanthonitschkea)My conclusion is thus that all Coronophoralean fungi so far known should betreated as one family (Nitschkiaceae) with Coronophora, Bertia, Gaillardiella,Nitschkia and Acanthonitschkea as the genera.The establishing of the correct name for the combined family offers its problem. To thosewho accept "Familie der Coronophoreen" (Hohnel 1907) as a valid name, Coronophoraceaeby priority becomes the correct name. But to those who—like myself—consider the Latinending as a sine qua non, Coronophoraceae and Nitschkiaceae are of the same age (Nannfeldt1932), and so we have to follow Miller (1949:121) in using Nitschkiaceae, for as far as I amaware he was the first to combine the two families.In this family, and especially in the "Nitschkieae",evolution and speciation haveworked with "Quellkorper", ascus structures and spore shape, whereas ascocarpshape and peridium structure have remained fairly constant. The family affords thusa striking contrast to another aberrant, most characteristic and homogeneous groupof true Pyrenomycetes recently studied by me, viz. Boliniaceae with Camarops asthe sole genus (Nannfeldt 1972). In that family asci and spores are practicallyidentical in all species, whereas perithecial shape and stromatal size and shape showenormous differences, the stromatal shape varying from almost valsoid to xylarioid,but the variation in stromatal structure is still kept within narrow limits.It remains to discuss the taxonomic position of the Coronophorales(=Nitschkiaceae). To-day considerably more is known about the evolutionarytrends within the Ascomycetes than it was well 40 years ago. One of the salientfeatures of the Coronophorales, the cleistocarpy, is now known to have evolvedrepeatedly and is not eo ipso a sign of high taxonomic rank (comp. e.g. Cain1972:3-5; Miiller & Arx 1973:96). The abortive apical ascus apparatus is also anobviously polyphyletic phenomenon and in our case a natural consequence of thecleistocarpy. The recognition of the "Diaporthe Type Centrum" (Luttrell) makes itpossible to connect the Coronophoralean locule with more "normal" ascohymenialtypes.The features of our group are thus no longer so strange as originally thought, andits place among the true (ascohymenial and unitunicate) Pyrenomycetes seemsfirmly established. Here it should be understood that, in my opinion, there are noconvincing facts in favour of the hypothesis by Chadefaud and his school thatunitunicate asci have evolved polyphyletically from bitunicate. Recent investigationson the fine structure of the ascus walls make such repeated transitions evenmore unlikely (comp. e.g. Griffith 1973).Svensk Bot. Tidskr. 69 (1975)