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

302 J. A. NannfeldtThe shape of the (mature) ascus is as a rule ± clavate to fusiform with the sporesdisorderly in several rows. In a few species they are ± cylindrical, thus in N. affinis(Fig. 3j), where they are rather truncate, and in N. uniseriata (Fig. 3i), where theeight spores are uniseriate and often transversely orientated. Tendencies to transversespore orientation are pronounced in both Coronophora and the Nitschkieae,thus in Coronophora annexa (Figs. 3a, b) with its polysporous asci and allantoidspores, and in an early stage in Ac. foveolata, when the eight spores are alsouniseriate.Number of spores. True polyspory (sensu Martens 1937) is common within theCoronophorales, and the number of spores per ascus is then often about 32.All species of Coronophora s.lat. are polysporous. To judge from the literature(e.g. Hohnel 1906, 1907; Munk 1957) the number of spores should normally be about32, but one (anonymous) species illustrated by Munk (I.e. fig. 111c) seems topossess only about 16 spores, and C. annexa as illustrated by Miller (1949:100 fig.31) shows much more than 32. My own observations on the latter species (Krieger,F. sax. 968) indicate that the number often approaches 64, but that some asci haveonly about 32. About 64 seems to be the normal number in C. gregaria (severalcollections).In Bertia moriformis the asci are 8-sporous, and so they are in the majority of theNitschkieae, but six species have about 32 spores per ascus, viz. Ac. pulchella, N.affinis, N. callista, N. leonensis, N. multiasca, and N. similis. Deviations from evenmultiples are not rare and in some species rather the rule. Thus in N. affinis and N.leonensis numbers about 25 seem to be the most common, but in the latter speciesI have observed numbers up to about 32 and down to about 16.N. broomeiana offers an extreme case not only by the high number of spores(>200) per ascus but also by their extraordinary and most characteristic arrangement,excellently described by Fitzpatrick (1924:108): "in several longitudinal rows,each spore lying obliquely with its lower end towards the ascus wall and its upperend towards the interior". I know of only one similar arrangement, and that waskindly pointed out to me by Dr. N. Lundqvist, viz. the oblique orientation of thespores in the young ascus of Podospora setosa (Wint.) Niessl (comp. Lundqvist 1972pi. 28 fig. d).My new African Nitschkia deviates in the opposite direction. Though 8 spores areformed in the ascus, only four of them reach maturity (hence the epithet tetraspora),become fusiform and get a coloured wall. The remaining four (as a rule the basalones) remain as acicular to narrowly fusiform, very thin-walled bodies withhomogeneous plasma and sometimes a spurious septum. They are best seen just afterthe deliquescence of the ascus wall, as they deliquesce later soon themselves.Spore size, shape, septation and wall. The spores are mostly relatively small, suballantoidto boomerang-shaped, until late or permanently continuous with thin,Svensk Bot. Tidskr. 69