Encalypta

Encalypta View in CoL

The complete series of 2 µm sections show the principally similar pattern in peristome development in four species of Encalypta . Selected photographs from these series were obtained for three samples of E. procera from two populations, two samples of E. longicollis from one population, four samples of E. rhaptocarpa from two localities and one sample of E. vulgaris ; they are given in Figs. 2 View Fig , 3 View Fig , 5 View Fig .

The developmental stages show in these figures start either from the “fundamential cross” or from eight-cells pattern where four endothecial and four amphithecial cells are differentiated. Downwards to juvenile sporophyte, the successive series present patterns characterized by peristomial formulae: 1, 2:1, 2:2:2, 4:2:2, with some deviations.

Longitudinal sections available for some species indicate the position of respective transverse sections, calculated as the difference between given section and by first section where endothecium is seen, and multiplied by 2 µm (the thickness of sections).

As the series might not cover the latest stages of peristomial development occurred, e.g., during sporogenesis time, we supplemented the series of transverse sections with SEM observations of inner (ventral) surface of basal parts of teeth. The occurrence of anticlinal divisions, albeit partly fairly irregular, indicates the delayed divisons in IPL cells of proximal part of teeth in all species of Encalypta . At the same time, middle, and moreover, distal parts of inner surface of teeth indicate that the formula 4:2:4 is performed only in proximal part of peristome, while more distally the formula remains to be 4:2:2.

Species-specific characteristics are listed briefly for individual species, based on these few studied specimens.