PLAGIOMNIUM DRUMMONDII (BRUCH ET SCHIMP.) T. J. KOP. – A NEW SPECIES OF MOSS FOR THE FLORA OF UKRAINE

Abstract

Background. Plagiomnium drummondii (Bruch et Schimp.) T. J. Kop. belongs to Mniaceae Schwägr.: section Plagiomnium T. J. Kop. This Holarctic hemiboreal species has a wide range but is rare in most regions. It is widespread in North America and is very rare in Europe (south-eastern Finland, southern Latvia, Serbia, northern and central parts of European Russia). The main limiting factors of distribution are the low competitiveness, the reduction of areas of ancient forests and the general climate change.
Materials and Methods. The moss sample was found on the territory of the “Roztochchya” Nature Reserve, on the site of a 40-year-old felling of the Stradch Educational and Production Forestry Plant (Yavorivskyi District, Lviv Region). The species of moss was identified using appropriate descriptions and keys. Morphometric analysis of plants (length of shoots and setae, sizes of leaves and capsules) was performed on the stereo binocular “Stemi 2000-C” (Carl Zeiss). The size of leaf cells and spores was determined using the Motorized Fluorescence Microscope Axio Imager M1 (Сarl Zeiss).
Results. The first record of a new moss species, Plagiomnium  drummondii (Bruch et Schimp.) T. J. Kop. has been reported for the flora of Ukraine. Short morphological characteristics, differences from similar typical forest moss species Plagiomnium cuspidatum (Hedw.) T. J. Kop., ecological peculiarities, geographical distribution, and original illustrations of moss gametophyte and sporophyte from the Ukrainian sample are provided. Important morphological traits by which the moss P. drummondii was identified were based on the following features of the gametophyte: leaf shape and size, presence of teeth on the leaf margin, the shape of the mid-leaf cells and thickening of their walls, as well as on the features of the sporophyte such as the orientation of seta, the shape of the capsule and availability of papillae on spores.
Conclusions. P. drummondii cannot be unequivocally removed from the bryoflora of continental Europe; further studies of the identified moss specimens and the search for new localities are necessary. The identified moss samples are stored in the bryological herbarium of the Institute of Ecology of the Carpathians, NAS of Ukraine (LWKS).