Romanian Journal of Biology - Zoology
ROMANIAN ACADEMY Institute of Biology - Bucharest
2006, VOLUME 51, 1-2
ON THE SYSTEMATIC POSITION AND EVOLUTION OF THE BLACK-HEADED WAGTAIL
The paper deals with the variation existing in the groups of grey-headed and black-headed wagtails belonging to the species Motacilla flava, and briefly analyses the hybrids appearing between these groups. In the author’s view the black-headed wagtail feldegg has the rank of a real, valid, species and its name should be Motacilla feldegg Michachelles, 1830; it is a polytypical species and includes two subspecies, namely Motacilla feldegg feldegg and Motacilla feldegg melanogrisea Homeyer, 1878. On the other hand, the author agrees with the opinion that Motacilla flava dombrowskii Tschusi, 1903 is a valid, selfstanding subspecies, not a hybrid between Motacilla flava flava and Motacilla feldegg.
CHRYSOMELIDS (COLEOPTERA: CHRYSOMELIDAE) FROM THE SYLVOSTEPPE FORESTS OF ROMANIA
The paper presents new data regarding the leaf-beetles fauna in some sylvosteppe forests from Romania. A total of 68 species belonging to 36 genera and 9 subfamilies have been recorded. For each species, the examined material and general distribution are given. In addition, there are presented plants where some chrysomelid species were found.
A SURVEY OF THE COLLEMBOLAN FAUNA OF SOME AGROECOSYSTEMS IN A DIKE ISLAND OF THE LOWER DANUBE FLOODPLAIN (INSULA MARE A BRĂILEI)
The aims of the present study are: to quantify the collembolan richness diversity of various types of agroecosystems (meadows, arable land with wheat, corn and soybean and a forest plantation with Salix sp.); to determine the differences between collembolan communities in these types of ecosystems; to discover the environmental factors responsible for these differences. Hemisotoma orientalis (Stach, 1947) is reported for the first time in the Romanian fauna.
TAXONOMICAL STRUCTURE OF THE EPICRIINA AND GAMASINA MITES (ACARI-MESOSTIGMATA: EPICRIINA, GAMASINA) IN FORESTRY ECOSYSTEMS FROM BUCEGI MASSIF
MINODORA STăNESCU, VIORICA HONCIUC
This paper presents the structure of the Mesostigmata - Epicriina, Gamasina mites from three ecosystems with Picea abies, Abies alba and Fagus sylvatica. Species composition of edaphic mites showed the presence of the two suborders: Epicriina with one family (Epicriidae) and three species and Gamasina with 10 families (Parasitidae, Veigaidae, Ameroseiidae, Aceosejidae, Rhodacaridae, Macrochelidae, Pachylaelaptidae, Laelaptidae, Eviphididae and Zerconidae) with 39 genera and 96 species. The temporal dynamic shows the presence of a two periods of study. In first period were recorded 89 species and in the second one 81 species. The identified species were classified in the following trophical categories: predators, omnivorous, poliphagous and phytophagous.
THE MAIN ALIEN/INVASIVE INSECTS SPECIES IN ROMANIA
IRINA TEODORESCU, TRAIAN MANOLE, MARIA IAMANDEI
The data refer to 98 insect species belonging to Orthoptera, Blattaria, Thysanoptera, Homoptera, Heteroptera, Hymenoptera, Coleoptera, Lepidoptera and Diptera orders, from which, 43 can be considered invasive species. A number of 85 species are pests, 5 are vector and household species and 8 are useful species (parasitoid, predator, pollinator, silk worm).
DYNAMICS OF THE EURYGASTER NUMERICAL DENSITY, IN HIBERNATION AND IN WHEAT CROPS (BRĂILA COUNTY, ROMANIA, 1996-2003)
MARIA-ELENA TEODORESCU, IRINA TEODORESCU, VIOLETA POPESCU
Some investigations extended in time (1996-2003) and in space (crops and forests from Brăila County), on the most important pest for the cereals in Romania (Eurygaster integriceps) revealed the main factors, which determined his population’s dynamics. In the forests, differences between the adult’s densities registered in each autumn, and those in the next spring, in the hibernation places, were caused mainly by the non-biotic factors (floods, high temperature intervals in early spring, followed by sudden and sharp decreases of temperatures). More efficient, mortality in the forests was caused by the entomo-pathogenic fungous (during the warm and wet periods) and by the predators, in the warm autumns and springs. In the crops, mortality of the adults, larvae and eggs was caused mainly by the biotic factors (Scelionidae oophagous parasitoid), in comparison with non-biotic (strong wind, rain downpour, long drought).
THE BIOMASS OF ZOOBENTHOS IN THE IRON GATES I DAMLAKE (ROMANIAN STRETCH) IN 2002
We present in this paper the biomass of the invertebrate benthos, founded in the Iron Gates I damlake. In comparison with biomass value founded before the accumulation construction, the 2002 value is higher. The highest biomass values belonged especially to the species, primarily of fresh water, among the lamellibranchiate and gastropods. The Ponto-Caspian elements (gammarids, corophiids, isopods, polychaets) (secondarily of fresh water) had very rarely a significant contribution to the biomass of benthos invertebrates. In the two analyzed 2002 seasons, were observed (at the level of benthos populations) wide spatial and seasonal variations. From the spatial variation point of view, the numbers corresponding to the lake middle navigable zone situated on the first place. Seasonally, the highest biomass values were found on all analyzed profiles, usually in summer.
STRUCTURAL CHANGES CAUSED BY COPPER ACTION ON THE GILLS OF CYPRINUS CARPIO (PISCES-TELEOSTEI) JUVENILE FISHES
VIORICA MANOLACHE, VIRGINIA POPESCU-MARINESCU, MARIA NĂSTĂSESCU, DANIELA TEODORESCU, FLORIN AIOANEI, LUMINIŢA NISTOR
Our investigations on the action of various copper concentrations (0.1; 0.5; 1 mg/l) during various intoxication times (from 24 h to 7 days) upon Cyprinus carpio L. young fish gills revealed a number of important cell and tissue structural changes. Gill disorganization was such that it resulted in gill lamellae destruction by: cell hypertrophy, nuclei deformation and pycnosis, dilatation, even breaking of blood vessels endothelia and extravasations of blood from affected vessels. The found changes are, generally, directly related to toxicant concentration in water and to intoxication time.
BIPHASIC DYNAMIC OF THE “IN VIVO” GLUCOSE-INDUCED INSULIN SECRETION IN MICE AND HAMSTERS
IOANA TRANDABURU, DORINA MIRANCEA, MIRELA ARGINT, TIBERIU TRANDABURU
A biphasic pattern of insulin secretion stimulated with glucose, similar to those recorded in perfused rat and human pancreas and in the perifused rat and mice pancreatic islets, was described in hamsters after i.p.injection of a single hexose dose. In the two rodent studied (mice and hamsters), the dose of 3.3 g glucose/kg body weight has induced biphasic variations of the amounts of secretory granules produced by the B-cells within a 90 min. time - interval. In its turn, the B-cell response to glucose has evoked in the next few minutes a similar biphasic dynamic of glycemia in both species. The histochemical observations on the pancreatic islets, corroborated with the glycemia values at 90 min. after hexose administration, supported notable differences between mice and hamsters as regard the recovery rate of B-cells from the second phase of hormone secretion. The results are discussed in connection with the findings of other authors.
THE SEQUENCE OF INFRASTRUCTURAL EVENTS OF THE HAIR FOLLICLE MORPHOGENESIS DURING GOLDEN HAMSTER (MESOCRICETUS AURATUS) EMBRYO DEVELOPMENT
DORINA MIRANCEA, NICOLAE MIRANCEA
In this paper we reported on hair follicle morphogenesis during embryo development of the golden hamster (Mesocricetus auratus). Hair follicle morphogenesis starts when epidermal basal cells proliferate accelerated to form an epithelial cell conglomerate. Subsequently, the epithelial cells of such cell conglomerate will migrate profoundly into subjacent dermal tissue, but remaining cohesive each other by desmosomal junctions keeping the continuity with the epidermis from which this formed, the whole ansamble taking the form of an epithelial column (cylinder). The lower most part of the epithelial column become dilated (bulbar aspect) and an invagination is formed – a virtual cavity – within the dermal mesenchymal cells will immigrate to form dermal papilla and together with surrounding cells will form the hair. Some infrastructural aspects of the golden hamster hair follicle will be compared to that of mouse hair follicle. While generally the golden hamster morphogenesis of hair follicle follows the mammalian pattern, some ultrastructural particularities are significant.
© 2008 Institute of Biology. All right reserved.
Send mail to firstname.lastname@example.org
with questions or comments about this web site.