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The Genus Bilabrella Lindl. (Orchidaceae, Habenariinae): General Characteristic and Research History of The Genus

Abstract

The genus Bilabrella (Habenarinae, Orchidaceae) was described by Lindley in 1834, but within next years, different authors incorporated it as the section of the genus Habenaria Willd. From 2003, Szlachetko and Kras stated that there were no grounds for distinguishing the sections Bilabrellae and Replicatae. They restored the genus Bilabrella, transfering to it 93 species from the section Replicatae and four species new to science were described. The poor condition of the old plant materials, the lack of some type specimens for many species described by Schlechter and problems with a series of transitional forms between some species are only few reasons, why the revision of the genus has not been published so far. Bilabrella comprises orchids found in Sub-Saharan Africa, Madagascar and neighbouring islands. Bilabrella differs from other Habenariinae in its unique combination of features

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Late Pleistocene Birds from Binagada (Azerbaijan) in Collection of the National Museum of Natural History (Kyiv, Ukraine)

Abstract

Bird fossils from the Late Pleistocene locality Binagada, deposited kept in the National Museum of Natural History in Kyiv (Ukraine), are described in this paper. Twenty six bird species are identified, including five (Little Stint, Great snipe, Jack snipe, White-winged lark and Rosy Starling) which have not been previously known from this locality. The validity of extinct species Calidris binagadensis (Serebrovsky, 1940) is confirmed and the invalidity of subspecies Anas platyrhynchos paleoboschas Serebrovsky, 1940 is shown. The finding of Rosy Starling fossils in Transcaucasian region confirms the range reduction of this species at the end of Pleistocene.

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Herbaria of the Prussian physician Boretius (1694-1738) in the Herbarium WA

Abstract

Pre-Linnaean herbaria have a growing value for botanists and historians of science. A unique example is a four volume herbarium from the early 18th century preserved in the archives of the Herbarium of the Faculty of Biology, University of Warsaw. They consist of one, originally five volume set. We proved that the plants had been gathered by the famous naturalist Georg Andreas Helwing (1666-1748), and his son-in-law, Matthias Ernst Boretius (1694-1738), and they annotated and classified the exhibits. Boretius was born in Prussia, in Lec (now: Giżycko). He acquired his academic training in Königsberg and Leiden, and deepened it by scientific travels. He was the first in Masuria to promote vaccination against smallpox. Earning the reputation of a distinguished scholar, he was appointed Royal Physician and Crown Councilor of the Prussian court. He died in 1738 at the age of just 44, leaving the herbarium vivum – a magnificent remnant of his times. There are over 900 cards with glued specimen, signed in three languages: Latin, German and Polish. It includes vascular plants, liverworts, true mosses, clubmosses, algae and macrofungi. Boretius implemented the system made known by the French botanist Joseph Pitton de Tournefort (1656-1708). His system divided the plant world into 22 classes, based on flower morphology but also retaining the traditional split into trees, shrubs and forbs. The choice of this arrangement by Boretius was an innovation; the earlier plant collections of his tutor Helwing lacked any attempt to classify plant species.

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Population surveys of Nile crocodiles (Crocodylus niloticus) in the Murchison Falls National Park, Victoria Nile, Uganda

Abstract

1. A 12-month-long survey (April 2013 to March 2014) for Nile crocodiles (Crocodylus niloticus) was conducted along a section of the Victoria Nile/Ramsar site of Murchison Falls National Park, in order to update the historic information on crocodile populations in the area, locating nesting areas, determining seasonality patterns and habitat use, and assess the current abundance and the population size trends since the 1960s. The methods employed included visual encounter surveys, transect counts and opportunistic methods, by using boats. 2. In general, there were diurnal and seasonal fluctuations in the number of crocodile sightings. The crocodile sightings peaked between the months of June and August, with the highest mean number of sightings encountered on any single day being 67 (in July 2013), and the second peak was between January and March with the highest mean of 118 recorded in January 2014. The second peak also coincided with the crocodile breeding season. This clearly shows that the distribution of the sub-population sampled followed a climatic regime. 3. Crocodiles were observed most frequently in water (37%). Grassy banks, islands, river mouths and sandy banks constituted about 47% of the habitats utilised by the crocodile population. Although basking was the most frequent type of activity performed by crocodiles (50%) over the entire survey period, their key activities varied significantly from month to month. Nesting was very visible during the last quarter of the year and the first quarter of the New Year. 4. There was a clear decline of the abundance of crocodiles in this population between 1960s and nowadays. This declining trend was obvious also taking into account the various survey methodologies employed over the decades.

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Effect of food types on competitive interaction between Aedes aegypti (LINNAEUS, 1762) and Ae. albopictus (SKUSE, 1894) (Diptera, Culicidae): a proximate level appraisal

Abstract

Competitive interactions between coexisting Aedes aegypti and Ae. albopictus have been implied as a crucial factor shaping life history traits and population characteristics. The overlap in resource requirements and similarities in the life history strategies of the two Aedes mosquitoes form a basis for competitive interactions. In the present study, the role of the food quality of the larval habitats in influencing the outcome of competition between Ae. aegypti and Ae. albopictus is evaluated to highlight food quality as a basis for asymmetric competitive outcomes. Instar I larvae of the two mosquitoes were reared using conspecifics or heterospecifics of constant size and equal ratio with four different food types: boiled rice, boiled pulses, a mixture of boiled rice and pulses, and fish food. Competitive interactions were evaluated using age at pupation (AP), pupal weight (PW), dry adult weight (AW) and wing length (WL) with respect to intra- and interspecific competition for the two sexes of each mosquito species. The results show that Ae. albopictus developed faster but achieved a smaller size compared to Ae. aegypti under interspecific competition conditions, the extent of the difference varying significantly with the food type. Given the variety of food resources available in the small container larval habitats, the results of the study imply that food quality may act differentially with respect to larval development and adult body size, depending on the conspecifics or heterospecifics and on the sex of the species concerned. The dominance of one species over the other may also be a consequence of the resource utilization pattern that varies in the larval habitats.

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Distribution of the Common Adder Vipera berus and the Slow Worm Anguis fragils in Silesia, SW Poland

Abstract

During the years 2004-2008 the distribution of the Common Adder and the Slow Worm were studied in Silesia through questionnaire directed to forest inspectorates (n=871); 83.8% of them responded. These data were tested through field work in several randomly selected inspectorates. Both species were found to be widespread in the region, with a few strongholds identified in Sudety Mts. and larger forest complexes. The Common Adder was recorded in 68.5% of forest districts which responded, while the Slow Worm – in 73.6% of those districts. Changes in distribution and population trends could not be derived, since no reliable data were available from previous years.

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Raptors in Bosnia and Herzegovina - their status and perspectives for monitoring development

Abstract

In the last 150 years, 49 raptor species belonging to the families Pandionidae, Accipitridae, Falconidae, Tytonidae, Strigidae and Laniidae have been recorded in Bosnia and Herzegovina. However, little is known about their populations. In comparison with historical data, their status has changed significantly, while nine species became extinct or probably extinct as breeders. In this paper, data on the present status of raptor populations is presented, as well as problems and the possibilities of developing species monitoring in Bosnia and Herzegovina. So far, no raptor monitoring has been established in the form of a long-term programme. The establishment of such programme is hampered by a number of reasons (lack of observers, lack of financial resources, lack of experience and knowledge, etc.). Monitoring of raptors in Bosnia and Herzegovina is needed to improve knowledge of the local populations as well as to protect these birds and their habitats. Also, this programme would be significant for the studies concerning the construction of various facilities (e.g. wind turbines). One of the important points of the development programme is to mobilize international cooperation and projects to solve current problems

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Effects of land use history and inoculation with Fusarium oxysporum f. sp. cucumberinum Owen on soil nematodes communities

Abstract

A pot culture experiment was carried out to study the effects of land use history and inoculation with Fusarium oxysporum f. sp. cucumberinum Owen (Foc) on soil nematodes communities during the cucumber growing season in 2007. The results showed that land use history and inoculation had significant effects on the abundance and diversity of soil nematodes. Bacterivores were found to be the most dominant group in this study. Irrespective of inoculation, numbers of fungivores, plant-parasites and values of trophic diversity index (TD) and plant-parasites index (PPI) were greater in greenhouse soils (GH) than in open field vegetable soils (OF) during the growth period of cucumber. While, the number of omnivores-predators and values of richness (SR) and maturity index (MI) presented an opposite trend. Foc inoculation had noticeable effects on numbers of plant-parasites and some taxa, such as Helicotylenchus, Epidorlaimus at flowering stage and Aphelenchus, Tobrilus at fruiting stage. Besides, inoculation significantly affected values of PPI at flowering stage and TD at fruiting stage, respectively. The faunal analysis showed that soil food web in GH was highly disturbed and in OF was degraded.

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The evolutionary ecology of interactive synchronism: the illusion of the optimal phenotype

Abstract

In this article, we discuss some ecological-evolutionary strategies that allow synchronization of organisms, resources, and conditions. Survival and reproduction require synchronization of life cycles of organisms with favourable environmental and ecological features and conditions. This interactive synchronization can occur directly, through pairwise or diffuse co-evolution, or indirectly, for example, as a result of actions of ecosystem engineers and facilitator species. Observations of specific interactions, especially those which have coevolved, may give the false impression that evolution results in optimal genotypes or phenotypes. However, some phenotypes may arise under evolutionary constraints, such as simultaneous evolution of multiple traits, lack of a chain of fit transitional forms leading to an optimal phenotype, or by limits inherent in the process of selection, set by the number of selective deaths and by interference between linked variants. Although there are no optimal phenotypes, optimization models applied to particular species may be useful for a better understanding of the nature of adaptations. The evolution of adaptive strategies results in variable life histories. These strategies can minimize adverse impacts on the fitness of extreme or severe environmental conditions on survival and reproduction, and may include reproductive strategies such as semelparity and iteroparity, or morphological, physiological, or behavioural traits such as diapause, seasonal polyphenism, migration, or bet-hedging. However, natural selection cannot indefinitely maintain intra-population variation, and lack of variation can ultimately extinguish populations.

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The Devil in the Deep: Expanding the Known Habitat of a Rare and Protected Fish

Abstract

The accepted geographic range of a species is related to both opportunity and effort in sampling that range. In deepwater ecosystems where human access is limited, the geographic ranges of many marine species are likely to be underestimated. A chance recording from baited cameras deployed on deep uncharted reef revealed an eastern blue devil fish (Paraplesiops bleekeri) at a depth of 51 m and more than 2 km further down the continental shelf slope than previously observed. This is the first verifiable observation of eastern blue devil fish, a protected and endemic southeastern Australian temperate reef species, at depths greater than the typically accepted depth range of 30 m. Knowledge on the ecology of this and many other reef species is indeed often limited to shallow coastal reefs, which are easily accessible by divers and researchers. Suitable habitat for many reef species appears to exist on deeper offshore reefs but is likely being overlooked due to the logistics of conducting research on these often uncharted habitats. On the basis of our observation at a depth of 51 m and observations by recreational fishers catching eastern blue devil fishes on deep offshore reefs, we suggest that the current depth range of eastern blue devil fish is being underestimated at 30 m. We also observed several common reef species well outside of their accepted depth range. Notably, immaculate damsel (Mecaenichthys immaculatus), red morwong (Cheilodactylus fuscus), mado (Atypichthys strigatus), white-ear (Parma microlepis) and silver sweep (Scorpis lineolata) were abundant and recorded in a number of locations at up to a depth of at least 55 m. This underestimation of depth potentially represents a large area of deep offshore reefs and micro-habitats out on the continental shelf that could contribute to the resilience of eastern blue devil fish to extinction risk and contribute to the resilience of many reef species to climate change

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