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This paper describes the first study of algae assemblages in 20 caves in the Krakowsko-Częstochowska Upland (Southern Poland), in the period between 2005-2006. The investigations showed mostly on epilithic algae and their subaeric habitats (rock faces within caves and walls at cave entrances). The morphological and cytological variability of algae were studied in fresh samples, in cultures grown on agar plates and in SPURR preparations. A total of 43 algae species was identified, mostly epilithic species and tolerant of low light intensities. The largest group was formed by representatives of the division Chlorophyta (24 species), and then the division Chrysophyta (Heterokontophyta) - 17 species, with 9 species belonging to the class Bacillariophyceae, 7 species - Xanthophyceae and 1 species representing the class Eustigmatophyceae. Dinophyta (2 species) constituted the last and the smallest group. Among the collected algae, the following species deserve special attention: Thelesphaera alpina, Bracteacoccus minor, Trachychloron simplex, Tetracystis intermedia and T. cf. isobilateralis. The last species was not earlier found in Europe. Identification of species was greatly aided by examination of cell ultrastructure, which provided an array of further features, increasing chances of correct species identification. Furthermore, the studies focused that algae, although usually remaining under dominance of cyanobacteria, excellently differentiate this special area and even enrich it.
Algological studies of the River Silnica performed on 25 May and 5 June 1995 recorded the presence of 88 taxa. Among them there are a number of rare and interesting species, such as Navicula Integra (W.Smith) Ralfs, N. rhynchocephala Kütz., Neidium opulentum Hust., Gyrosigma acuminatum (Kütz.) Rabh., Rhoicosphaenia abbreviata (Ag.) Lange-Bert., Frustulia vulgaris (Thw.) De Toni, and Caloneis amphisbaena (Bory) Cl. The flora occurring in the upper part of the river can be distinguished by a rich group of species and was of the most natural character, contrary to other sections of the river which are polluted, this being shown by the number of diatoms and ultrastructures of Cladophora glomerata (L.) Kütz. obtained.
Basicladia chelonum (Collins) W.E. Hoffmann and Tilden (1930) principally known from North America and Hawaii was recently (2004) found in Cuba (Caribbean) from artificial pool growing on shells of musk turtles (Trachemys decussata Gray). Specimens collected in Cuba were subjected to detailed examinations also using a transmission electron microscope. On one hand, these studies confirmed many features of this species previously described by earlier authors in the specimens from Texas. On the other hand, the present studies revealed structures unknown so far (pyrenoid structure), which allowed for new analysis of this species. These investigations also have shown that Basicladia chelonum exhibits close similarity to the genus Cladophora and other representatives of the class Cladophorophyceae. The similarities include : siphonocladous level of organization of thallus, numerous chloroplasts forming a network and other structures. Conversely, the pyrenoid in vegetative cells of Basicladia chelonum distinguishes it markedly from representatives of the genus Cladophora, which have bilenticular pyrenoids divided into two hemispheres by a single thylakoids and each hemisphere is covered by a bowlshaped starch grain (Van Hoek et al. 1995). Since in Cladophora the ultrastructure of the pyrenoid is highly constant and characteristic, this contrasts with the genus Basicladia and, therefore, more firmly establishes position of the latter as an independent unit within Cladophorophyceae.
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