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Lower Cretaceous ammonites from the Artemisa, Polier and Lucas Formations of the Pinar del Rio province, are described. The assemblage comprises 47 species, including four new: Karsteniceras polieri, Crioceras pinarensis, Acrioceras (Paraspinoceras) rosariensis and ?Pleurohoplites machini. Some of them are common for Cuba, Mexico and south Andes. Typical west - Tethyan ammonites form a noticeable part of the Cuban assemblage.
Using mist-nets, we studied the composition of bat assemblages in four distinct secondary habitats of the Sierra del Rosario Biosphere Reserve, Cuba. For each individual captured we recorded reproductive condition, seeds in feces, and pollen species. Of the 550 bats captured during 41 nights of sampling, 97% belonged to six species of Phyllostomidae, and 88.7% belonged to just three: Artibeus jamaicensis, Phyllonycteris poeyi and Monophyllus redmani. The total number of captures varied among the four sites, being higher in the two more disturbed sites although this may have been an artifact of the use of ground-level mist-nets in vegetation of different structure. However the higher capture frequencies found in these sites could be related to the availability of understory fruits and the less dense understory vegetation too, allowing some species to exploit resources farther from forest edges. On three sites, the captures included a common large frugivore, two common nectarivores, and two uncommon species. The species composition of these assemblages resembled that observed in previous studies in the better-conserved core zone of the Biosphere Reserve. This implies that food availability and vegetation structure might be more important influences than the conservation level of vegetation on the composition and structure of assemblages of Cuban phyllostomids. In spite of the reduced diversity of the assemblage we studied compared with mainland assemblages, the relative abundances of Cuban bats tend to be higher than some continental ones. This could be related to lower bat diversity and a higher degree of gregariousness of the Cuban phyllostomids.
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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