B. Papp szerk.: Studia Botanica Hungarica 39. 2008 (Budapest, 2008)

Erzberger, P.; Schröder, W.: The genus Schistidium (Grimmiaceae, Musci) in Hungary

From S. rivulare (which has not yet been found in Hungary - Fig. 28), it can be distinguished by gametophytic characters, e.g. the entire leaf margins (except at apex - compare Figs 27C and 28B) and the more shallowly keeled, symmetric leaves (sharply keeled and often asymmetrically secund in S. rivulare: Fig. 28A), and sporophytic characters, particularly the patterns of exothecial cells and seta surface cells (exothecial cells isodiametric and incrassate in S. rivulare: Fig. 28D, E), shortly elongate and rather thin-walled in S. platyphyllum (Fig. 27F); seta surface cells + strongly elongate, incrassate in S. rivulare (Fig. 28F), shortly elongate to isodiametric and rather thin-walled in S. platyphyllum: Fig. 27G), and by the absence of stomata. Habitat: In Scandinavia S. platyphyllum grows on base-rich or calcareous rocks in or beside streams (rarely submerged), occasionally in fissures of irrigated ledges and cliffs in the mountains, or on regularly inundated sea- or lake-shore boulders (BLOM 1998, WEIBULL 2006). In NW Germany it was found mainly on siliceous blocks at the rivers Elbe, Weser, Ems, Rhine and some of their tributaries (MEINUNGER and SCHRÖDER 2007). The Hungarian habitat on block edging at the banks of the Danube corresponds to the German type of lowland habitat on river banks. Vertical distribution: 100 m a.s.l. Distribution: In Hungary at present known from a single collection. Specimen examined: Danube inundation area: 8380/2 Comit. Pest. In saxis irrigatis Danubii adurb. Szentendre, 100 m, 11.08.1994, leg. B. Papp and M. Rajczy (sub S. rivulare), rev. P. Erzberger 2007, conf. W. Schröder 2007, BP 163340. The plants conserved in this specimen were growing on stones in the inundation area at the Danube in the small island "Pap-sziget" near Szentendre (B. Papp, ex verbis). A recent search of the site and of similar places near Szentendre and in the Danube valley between Szob and Vác by the first author was unsuccessful. Fig. 29. Distribution of Scbistidium platyphyllum