The highest altitude recorded for an amphibian in Europe (west of the Caucasus) is 2965 m. It refers to the "lacs de Cambalès" according to an old reference. However, these lakes are all situated below 2600 m, while the altitude corresponds exactly to that of the summit of the Pic de Cambalès. We undertook an almost complete survey of ponds in a 2.5 km radius from the Cambalès peak, and complemented these data by fieldwork in a larger portion of the Central Pyrenees. Based on our observations in a total of 325 lakes and ponds we conclude that no water bodies above 2800 m exist in the Cambalès area, and that no water bodies above 2600 m are populated by Rana temporaria. The highest amphibian record was that of a single R. temporaria specimen at 2569 m, while the highest reproducing population was found at 2516 m. Highest records of other amphibians were 2516 m (Alytes obstetricans), 2160 m (Bufo bufo), 2259 m (Euproctus asper), and 2142 m (Salamandra salamandra). The presence of ice-free water bodies during a sufficient amount of time for larval development is probably the limiting factor for elevational distribution of Pyrenean amphibians, and the adequate conditions are usually not met above 2500 m in this massif. In contrast, in the Alps, ponds at higher altitudes are often protected by much higher surrounding peaks, which leads to higher elevational occurrence of amphibians. The Italian Laghi di Tre Becchi (up to 2742 m) are therefore the highest locality of a reproducing anuran population in Europe west of the Caucasus.
Deserts and semi-deserts, such as the Sahara-Sahel region in North Africa, are exposed environments with restricted vegetation coverage. Due to limited physical surface structures, these open areas provide a promising ecosystem to understand selection for crypsis. Here, we review knowledge on camouflage adaptation in the Sahara-Sahel rodent community, which represents one of the best documented cases of phenotype-environment convergence comprising a marked taxonomic diversity. Through their evolutionary history, several rodent species from the Sahara-Sahel have repeatedly evolved an accurate background matching against visually-guided predators. Top-down selection by predators is therefore assumed to drive the evolution of a generalist, or compromise, camouflage strategy in these rodents. Spanning a large biogeographic extent and surviving repeated climatic shifts, the community faces extreme and heterogeneous selective pressures, allowing formulation of testable ecological hypotheses. Consequently, Sahara-Sahel rodents poses an exceptional system to investigate which adaptations facilitate species persistence in a mosaic of habitats undergoing climatic change. Studies of these widely distributed communities permits general conclusions about the processes driving adaptation and can give insights into how diversity evolves.
A new harpactorine reduviid, Camptibia obscura, gen. et sp. n., from China is described. A key to related genera is provided. The functional morphology of the fore legs of this species is discussed.
The claim by many authors that Spinitectus inermis (Zeder, 1800), a narrowly specific parasite of European eels Anguilla anguilla (L.), is a rare species is considered at three levels: its geographical range, its frequency of occurrence compared to other eel parasites and its relative abundance in component communities. The parasite is widely distributed in freshwater throughout the European range of the eel but its occurrence is erratic and unpredictable, being known from only 8 countries. Surveys of eel parasites in the United Kingdom and in Continental Europe show that it is present in only 13% of British and 29% of continental localities. This satisfies one of the criteria for rarity. When present, its prevalence ranges from 1.8% to 43.3%, so it can be considered rare in some localities but in a few it may be common and on occasion it may be the dominant species in the gastro-intestinal community. Populations of S. inermis are almost always characterised by high levels of overdispersion, even at low prevalence. The species also displays an ability to colonise a locality following introduction there. Overall it meets many of the criteria of a rare species including a restricted distribution and a low frequency of occurrence and so it can be considered to exhibit diffusive rarity.
Safranal and crocin are biologically active compounds isolated from Crocus sativus L., commonly known as saffron. Clinical trials confirm that saffron has antidepressant effect, thus being a potential valuable alternative in the treatment of depression. The aim of the present study was to determine, whether systemic administration of safranal and crocin can influence the metabolic activity of CYP3A, CYP2C11, CYP2B, and CYP2A in rat liver microsomes (RLM). The experiments were carried out on male Wistar albino rats intragastrically administered with safranal (4, 20, and 100 mg/kg/day) or with intraperitoneal injections of crocin (4, 20, and 100 mg/kg/day). Our results demonstrate the ability of safranal and crocin to increase the total protein content and to change the metabolic activity of several CYP enzymes assessed as CYP specific hydroxylations of testosterone in RLM. Crocin significantly decreased the metabolic activity of all selected CYP enzymes, while safranal significantly increased the metabolic activity of CYP2B, CYP2C11 and CYP3A enzymes. Therefore, both substances could increase the risk of interactions with co-administered substances metabolized by cytochrome P450 enzymes., G. Dovrtělová, K. Nosková, J. Juřica, M. Turjap, O. Zendulka., and Obsahuje bibliografii