Botanica Lithuanica, Volume 12, Number 1

2006 m.

Research on protective belt and forest vegetation, significant to the scenery of the rivers Neris, Vilnia and Dūkšta, was carried out in 2001–2004. An evaluation of the ecoaesthetical quality of 25 sceneries of the rivers Neris, Dūkšta and Vilnia led to the determination that most (52 %) of the sceneries were picturesque. The species composition and aesthetical features of protective belt and forest vegetation were also evaluated. The ecoaesthetical quality of protective belt and forest vegetation and sceneries decreased when an abundance of alien plant species were present.

Keywords: scenery, forests, protective belts, aesthetical features, Lithuania.

A morphological study of the three species of Emilia Cass. in two different ploidy levels in Nigeria was performed. Both qualitative and quantitative characters were recorded. Characters of taxonomic value include the habit, bloom colour, colour and pubescence of the stem, differences in the margin of the leaves, corolla tube, style and stigma colours, pedicel length, capitulum length and breadth, the quantitative relationship of floret to involucral bracts, floret number, fruit number and size. E. praetermissa, the allotetraploid hybrid, is closely related to E. coccinea and E. sonchifolia – the other diploid relative. E. praetermissa has intermediate morphological and ecological characteristics. The morphological characters indicating E. praetermissa as an allotetraploid hybrid of E. coccinea and E. sonchifolia are bloom colour, corolla tube colour, and pedicel length. E. praetermissa behaves like a true allopolyploid in its habitat and ecological preferences. A new key to the Emilia species in Nigeria is included.

Keywords: qualitative characters, quantitative characters, taxonomy, diploid, allotetraploid, hybrid, ecology.

The reproductive phenology of eight medicinal plants in Omo Biosphere Reserve, Nigeria, was monitored monthly for twenty-four months. The flowering and fruiting periods of the species were cyclic. Dioscoreophyllum cumminsii, Irvingia gabonensis, and Xylopia aethiopica had well defined, predictable reproductive periods each year, while Carpolobia lutea, Sphenocentrum jollyannum, and Spondias mombin flowered and bore fruit either irregularly or continuously throughout the year. It is argued that while the ecological harvesting and sustainable management of Dioscoreophyllum cumminsii, Irvingia gabonensis, and Xylopia aethiopica would be easy, the reverse would be the case for Carpolopia lutea, Sphenocentrum jollyannum, and Spondias mombin.

Keywords: phenology, medicinal plants, ecological harvesting, sustainable management, Nigeria.

A detailed study of desmid flora was performed during 1997–1998 in the Dubičiai bog lakes (southeast of Lithuania), which had never been investigated by phycologists. The studies revealed 181 desmid taxa of which 27 are new to Lithuania. This paper is the first part of the material on new desmid species and contains information on morphometrics and the ecology data of five taxa: Pleurotaenium eugeneum, P. nodosum, Xanthidium armatum, Staurodesmus spencerianus, and Desmidium grevillei.

Keywords: desmids, lakes, bog, Dubičiai, southeast Lithuania.

This paper continues publication of the checklist of the Chlorococcales species recorded in the water bodies of Lithuania. The entire list comprises 283 species and intraspecific taxa ascribed to 13 families, 69 genera. The families Scenedesmaceae and Chlorellaceae, presented in the paper, comprise more than half (54 %) of coccoid green algae. Scenedesmus (66 species), Pediastrum (18), Oocystis (15), and Monoraphidium (12) are the most species-rich genera. The majority (88 %) of the recorded Chlorococcales species are rare in Lithuania, forty of them tend to develop in plankton abundantly. Frequent and rather rare species comprise 12 % of species richness, most of them develop in diferent types of water bodies and tend to dominate in the plankton. About 30 % of the recorded Chlorococcales species are known as frequent in the world. Over 30 % of species found in Lithuania show preference to all types of water bodies. Coccoid green algae flora is more diverse in lenthic waters than in lotic ones. Relatively high number Chlorococcales taxa tolerate brackish enviroment.

Keywords: Chlorococcales, Chlorophyta, checklist, water bodies, occurence, Lithuania.

During the 16th Symposium of Baltic Mycologists and Lichenologists held on 21–25 September 2005 in Cēsis, Latvia, 54 myxomycete and 1 acrasiomycete species were collected; 27 species were found in Latvia for the first time. Illustrations of some species new to the country are provided, and descriptions of the morphological details of critical specimens are given. The ecological peculiarities of Barbeyella minutissima, Cribraria purpurea, and Tubifera dictyoderma are discussed.

Keywords: slime molds, acrasiomycetes, ecology.