Observations on Syracosphaera rhombica sp. nov.

A spherical coccosphere and two collapsed coccospheres composed of monomorphic rhombic coccoliths were encountered in 2005 in the Java upwelling system of the SE Indian Ocean, while a further two specimens with elongate coccospheres were recently found in the Gulf of Mexico. All of the specimens were collected from the lower photic zone (75–160 m). The coccoliths possess a proximal flange, a slightly flared wall with a serrated distal margin, and a relatively plain central area structure comprised only of overlapping laths. The taxon appears to be an undescribed species of the Syracosphaera nodosa group, so we describe it herein as Syracosphaera rhombica sp. nov.     

Morphometry,biogeography and ecology of Calcidiscus and Umbilicosphaera in the South Atlantic

Here we present morphometrical evaluation, biogeographical distribution patterns and ecological information for five coccolithophore taxa (Calcidiscus leptoporus, C. leptoporus small, C. quadriperforatus, Umbilicosphaera foliosa and U. sibogae). This information is based on data obtained from surface sediments from the South Atlantic. The three Calcidiscus taxa can easily been distinguished by a combination of size and qualitative characters of their distal shields. Mostly encountered in the temperate to sub-polar regions C. leptoporus is the most abundant taxon and exhibits a negative correlation to temperature and salinity. Both, C. leptoporus small and C. quadriperforatus reach their maximum abundances also at higher latitudes and in the SW-African upwelling area. Their distributions therefore suggest preference for nutrient-enriched waters, which is also indicated by CCA. The two circular Umbilicosphaera species exhibit significant differences in coccolith morphology and show little overlap in size. Highest abundances are encountered in sub-tropical latitudes and are mainly derived from U. sibogae. In contrast, U. foliosa is present in very low abundances. Both species exhibit a preference for warm and oligotrophic conditions. However, U. foliosa increases in relative proportion to U. sibogae at the southernmost locations and in the Benguela upwelling. This could be interpreted as an affinity for slightly cooler and nutrient-enriched environments.     

Une entomopoxvirose chez l'orthoptèreAnacridium aegyptium

Résumé Un entomopoxvirus isolé de l'OrthoptèreAnacridium aegyptium L. est décrit. La réplication virale s'effectue dans le cytoplasme des cellules adipeuses. La microscopie électronique met en évidence les différentes séquences de la morphogénèse virale et l'inclusion des virions à l'intérieur des corps protéiques ovo?des. La microscopie électronique à balayage permet de visualizer quelques rares corps cristallins cubiques qui pourraient être les homologues des fuseaux accompagnant les entomopoxvirus décrits notamment chez certains coléoptères ou lépidoptères.      

Late Norian (Triassic) Radiolaria from the Kotel’nyi Island (New Siberian Islands,Arctic, Russia)

Two radiolarian assemblages were recovered from upper Norian strata of the Kotel’nyi Island (Russia); the first assemblage, from the Monotis zabaikalica Subzone (lower part of Upper Norian), is represented by Betraccium inornatum Blome, Dumitricaella (?) parva Sugiyama, Ferresium titulense Blome and 24 other species; the second assemblage, from the Monotis subcircularis Subzone (upper part of Upper Norian), is represented by Crucella sp. cf. C. angulosa Carter, Kahlerosphaera acris Bragin, K. sp. cf. K. parvispinosa Kozur & Mostler, Pseudohagiastrum crassum (Carter) and 11 other species. Both assemblages have common taxa with Upper Norian and Rhaetian radiolarian assemblages of British Columbia and they display clear Boreal features: low taxonomic diversity, abundance of taxa known from high-latitude regions, absence or rare presence of taxa known from low-latitude areas. The presence of early representatives of nassellarian genera Droltus and Parahsuum is very distinctive. Six new species are described: Pseudohagiastrum spinosum nov. sp., Cantalum boreale nov. sp., Plafkerium carteri nov. sp., Droltus guttaeformis nov. sp., Laxtorum blomei nov. sp., L. glacialis nov. sp.     

Pleistocene marine depositionalenvironments from Mauritius island,Indian Ocean

The Pleistocene elevated marine carbonate complexes on Mauritius island correspond to three types of depositional zones: (1) reef-crest zone, (2) backreef zone, (3) littoral zone.On reef crests, the primary frame-builders are scleractinian corals (Acroporidae, Faviidae, Poritidae) and crustose coralline algae. The secondary builders are encrusting Foraminifers (Homotrematidae) chiefly, Molluscs (Vermetidae), Bryozoans (Cheilostomata) and Serpulids. Associated internal sediments are coarse to fine sand-sized grainstones or packstones and wakestones. In decreasing order of abundance, skeletal elements include fragments of corals, branched and crustose red algae, Pelecypods, Gastropods, benthonic Foraminifera (Amphisteginidae, Peneroplidae, Calcarinidae, Nummulitidae, Alveolinidae and Homotrematidae), Echinoderms and Alcyonarians; the most abundant mud-sized grains are identified as tunicate spicules. Primary marine cements are needle, palisade, micrite and pelletal ones.The backreef zone is characterized by coarse tomedium grainstones, packstones and wakestones. In addition to pellets the most common components are skeletal in nature; they broadly show the same mode of occurrence as the reef-crest unit. Primary cements locally occur in packed fibrous or micrite form.In littoral areas, well-sorted grainstones to poorlysorted mudstones can be described. The distribution of the various categories of biogenic particles is dependent upon the extent of reef tracts; ancient beaches from narrow reefs are characterized by coralgal facies while consolidated muddy banks in large complexes display high amount of molluscan detritus. Primary cementation appears mainly to be the result of the precipitation of fibrous or micrite calcite.The morphology, biological associations andsediments of these Pleistocene limestones are homologous with those of the adjacent modern environments.     

Contribution of microscopic techniques to anatomical and morphological knowledge on Styrax officinalis L

The aim of this study was to precise anatomical and morphological features of the species Styrax officinalis with the help of current microscopic techniques, those features being of interest as valuable taxonomic characters. Typical hairy structures were observed on all surfaces of the aerial organs and their location, density and size were specified. Moreover, we demonstrated the occurrence of secretory glands in the leaf blades. These structures were revealed for the first time for this species.     

Monsoonal and other climatic influences on radiolarian species abundance over the last 35 ka,as recorded in core FR10/95-GC17, off North West Cape (Western Australia)

Species abundance counts from 46 surface sediment samples have been used to develop transfer functions for the reconstruction of salinity, and dissolved nitrates in the eastern Indian Ocean. Application of the functions to samples from deep-sea core FR10/95-GC17 [22° 07.74′ S, 113° 30.11′ E] shows that, offshore North West Cape, Western Australia, regional changes in salinity and the availability of dissolved nitrates were more significant in determining radiolarian species distributions over the last 35 ka than temperature. In addition, variations in the reconstructed data have been shown to reflect changes in marine currents and terrestrial rainfall over the study period.     

Heterogeneite des variations spectrales photoinduites vers 700 nm observees sur les membranes chlorophylliennes et les complexes chlorophylle-proteines isoles de divers organismes photosynthetiques

A heterogeneity of photoinduced spectral variations near 700 nm is observed at −196°C, by comparison of difference spectra obtained from several materials (two blue-green algae, Spirulina and Fremyella; a red alga Porphyridium and a higher plant, Nicotiana tabacum). The maximum of complexity is seen with Spirulina chlorophyllous membranes where three bands are detected at 718, 705 and 695 nm. These bands are recovered in relatively different amounts in two chlorophyll-protein complexes prepared after sodium dodecyl sulfate electrophoresis of Spirulina membranes.

The photoinduced changes near 700 nm with Spirulina membranes are reversible and seem to be synchronous and related to the bleaching of three different pigments. This spectral diversity for photosensizable pigments is comparable with the spectral heterogeneity of the major forms of the bulk chlorophyll. It is assumed that these pigments may play the same functional role. This assumption may be related to a possible heterogeneity of Photosystem I centres recently detected by Breton using linear dichroism method (Breton, J. (1977) Biochim. Biophys. Acta 459, 66–70).     

A new Oligocene-Miocene calcareous nannofossil species: Pontosphaera wallacei

A high-resolution study of sediments from DSDP Leg 72 Site 516 provided the opportunity to reconstruct a detailed biostratigraphy for the late Oligocene - early Miocene time interval. The detailed taxonomic investigation of calcareous nannofossils, performed by a quantitative analysis, highlighted the presence of a species of Pontosphaera that does not show the morphologic features of any recognized species of this genus. This species, which was previously classified as Pontosphaera sp., is here described as Pontosphaera wallacei nov. sp.     

A new Pennsylvanian (Late Carboniferous) – Permian foraminiferal genus (Lateenoglobivalvulina nov. gen., Biseriamminoidea) and its paleobiogeographic distribution

Lateenoglobivalvulina nov. gen. (Biseriamminoidea, Foraminifera) is introduced for biserial tests with a coiled initial part and a rectilinear evolute terminal part. The test has globular chambers progressively increasing in dimension. The shape of the test in axial section is isosceles triangle with a vertex angle of 90–100° or higher. The genus includes three species: Lateenoglobivalvulina spiralis (Morozova, 1949), L. pergrata (Konovalova, 1962) and L. arguta (Konovalova, 1962). The new genus belongs to the subfamily Globivalvulininae Reitlinger, 1950 emend. herein and to the family Globivalvulinidae Reitlinger, 1950, superfamily Biseriamminoidea Chernysheva, 1941. Lateenoglobivalvulina evolved from Globivalvulina Schubert, 1921 during the Pennsylvanian, it inhabited the Boreal Realm during the Pennsylvanian-Kungurian and it migrated to the southwest Paleotethys Ocean during the Sakmarian-Kubergandian.     

Improved Method for Isolating Synaptosomes from 11 Regions of One Rat Brain: Electron Microscopic and Biochemical Characterization and Use in the Study of Drug Effects on Nerve Terminal γ-Aminobutyric Acid in Vivo

A procedure is described for the rapid preparation of nerve ending particles (synaptosomes) from 11 regions of one rat brain. The synaptosomal fractions have been characterized by electron microscopy and determination of four marker enzymes, i.e., glutamate decarboxylase (GAD), acetylcholinesterase, succinate dehydrogenase, and glycerol 3-phosphate dehydrogenase. Comparison with a much lengthier standard (Ficoll-sucrose) preparation showed that the synaptosomal yield of the new procedure was substantially better as judged by both morphological evaluation and protein recovery. The improved synaptosome preparation was used for determination of regional gamma-aminobutyric acid (GABA) levels in synaptosomal fractions. The postmortem increase in GABA level during removal and dissection of brain tissue and homogenization and fractionation procedures could be minimized by rapid processing of the tissue at low temperatures and inclusion of the GAD inhibitor 3-mercaptopropionic acid (3-MP; 1 mM) in the homogenizing medium. The addition of GABA (0.2 mM) to the homogenizing medium did not alter the GABA levels in the synaptosomes, indicating that no significant redistribution of GABA occurred during subcellular fractionation in sodium-free media. Synaptosomal GABA levels determined in the 11 rat brain areas showed the same regional distribution as the GABA-synthesizing enzyme GAD. On the basis of these findings, it was suggested that the synaptosome preparation could be used to evaluate the in vivo effects of drugs on nerve terminal GABA. Treatment of rats with a convulsant dose of 3-MP (50 mg/kg i.p.) 3 min before decapitation significantly lowered synaptosomal GABA levels in olfactory bulb, hippocampus, thalamus, tectum, and cerebellum. The 3-MP-induced seizures and reduction of GABA levels could be prevented by administration of valproic acid (200 mg/kg i.p.) 15 min before the 3-MP injection. The data indicate that the improved synaptosome preparation offers a convenient method of preparing highly purified synaptosomes from a large number of small tissue samples and can provide useful information on the in vivo effects of drugs on regional GABA levels in nerve terminals.     

Evidence for the Existence of Imidazoline-Specific Binding Sites in Synaptosomal Plasma Membranes of the Bovine Brainstem

Abstract: Nonadrenergic imidazoline-specific binding sites were characterized pharmacologically in crude cerebral membrane preparations, but little is known about their subcellular localization in neurons. As in the brain-stem these sites are involved in cardiovascular regulation and peripherally imidazolines modulate neurotransmitter release, we tried to determine a possible (pre)synaptic localization in brainstem. We found a specific enrichment in (entire) synaptosome, purified synaptosomal plasma membrane (37 fmol/mg), and mitochondrial (83 fmol/mg) fractions as compared with other membrane fractions (3–8 fmol/mg). Synaptosomes appeared to be free of postsynaptic structures, and purified synaptosomal plasma membranes were devoid of mitochondrial material, as determined by electron microscopy and by comparison with the distribution of marker enzymes such as monoamine oxidase. These results show for the first time that these extramitochondrial imidazoline-specific sites are neuronal and are located on presynaptic terminals. We found high affinities for unlabeled p -iodoclonidine (subnanomolar), clonidine (0.2 n M ), and efaroxan (11 n M ), but idazoxan did not compete significantly for the p -[¹²⁵I]iodoclonidine binding in these membranes. Therefore, these sites can be classified as I₁ imidazoline receptors. In summary, we describe for the first time that high-affinity I₁ receptors of the bovine brainstem are located on (pre)synaptic membranes.     

Dysomma alticorpus,a new species of cutthroat eel from the Gulf of Aqaba,Red Sea (Teleostei: Synaphobranchidae)

The cutthroat eel Dysomma alticorpus n. sp. is described based on a single specimen collected in a trammel net at a depth of 350 m off Eilat, Israel, Gulf of Aqaba, Red Sea. The new species belongs to the Dysomma anguillare species complex, which comprises species possessing a well-developed pectoral fin, intermaxillary teeth, a uniserial row of 7–15 large compound teeth in the lower jaw (which may be followed by a few smaller teeth), and an anteriorly situated anus with the trunk shorter than the head length. It is characterised by a combination of the following characters: origin of the dorsal fin well anterior to the base of the pectoral fin, predorsal length 13.8% TL; preanal length 22.8% TL; three compound teeth on the vomer; head pores: IO 4, SO 3; M 6; POP 0; AD 1, F 0, ST 0; lateral-line pores: predorsal 4, prepectoral 8, preanal 14, total 57–58, the last at the posterior two-thirds of the total length; MVF 7–16–115; total vertebrae 115. Dysomma alticorpus n. sp. is compared with other species of the genus. A revised key to the species of the genera Dysomma and Dysommina is provided.     

L'intensité lumineuse,son influence sur la teneur en phosphore des carapaces d'Ostracodes

Actual and fossil shells of ostracodes have beenanalyzed with an electronic microprobe: all of them contain phosphorus. X—pictures teach us that the repartition of this chemical element is homogeneous in all the points of the shell. There is no relationship between phosphorus contents in the shells of ostracodes and salinity. In return, there is a relationship between phosphorus contents and temperature and, chiefly, organic phosphorus contents in the environment. However, it is interesting to observe that the analyzed shells of fresh-water ostracodes contain less phosphorus that the generality of the shells of marine ostracodes. The contents of organic phosphorus, in the biotope, depends on the growth of phytoplancton in the upper layers of water which needs a minimum light intensity.