Cell walls as taxonomic markers in Polish species of the genus Odontoschisma (Dum.) Dum. (Hepaticae, Cephaloziaceae)

Abstract

To get valuable diagnostic characters, the structure of cell walls was studied with use of two stains (Ruthenium Red -RR and Resorcine Blue - RB) and in polarized light. As far as the stem structure is concerned, European species of the genus <em>Odontoschisma</em> fall into two groups: in <em>Odontoschisma elongatum</em> and in <em>Odontoschisma macounii</em> a thick, frequently completely obscuring cell lumen, "lining layer" is present. It frequently, particularly after staining in RB, detaches from the rest of the cell wall. Such a layer is completely lacking in the two remaining species, viz. <em>O. sphagni</em> and <em>0. denudatum</em>. In polarized light only leaves of <em>O. sphagni</em> show a distinct bright border. The thin cellulose layer (bright in polarized light) embrace the angular thickenings in <em>0. sphagni</em> and <em>0. denudatum</em>, but is entering the inside of these thickenings in the two remaining species. Keys for determination of the four European species based on the staining properties of cell walls and their look in polarized light are provided.