Toxicidade aguda do sulfato de cobre e do extrato aquoso de folhas secas de nim para o caramujo (Pomacea canaliculata)

Snails can become an environmental and economic problem, causing substantial losses. The objective of this work was to estimate the acute toxicity of copper sulfate pentahydrate (CuSO4.5H2O) and the aqueous extract of dried neem leaves on snails (P. canaliculata) under laboratory conditions. In order to estimate the lethal concentration 50% (LC (I)50;96h), snails were exposed to six increasing copper sulfate concentrations (0.0; 0.01; 0.03; 0.05; 0.07 and 0.1 mg L-1) and six increasing concentrations of aqueous extract of dried neem leaves 0.0; 100; 125; 150; 175 and 200 mL aqueous extract of dried neem leaves L-1 water, equivalent to (0.0; 1.18; 1.47; 1.77; 2.06 and 2.36 mg azadirachtin L -1), in triplicate and one control treatment in an entirely random delineation. Estimated LC (I)50;96h, of copper sulfate was 0.02 mg copper sulfate L-1, with a 0.01 mg L-1 lower limit and a 0.03 mg L-1 upper limit. Estimated lethal concentration 50% of the aqueous extract of dried neem leaves was 142.75 mL L-1, equivalent to 1.68 mg L-1 of azadirachtine, with a 130.89 mL L-1 (1.54 mg L-1) low limit and 155.69 mL L-1 (1.83 mg L -1) as the upper limit.

Life mode of in situ Conularia in a Middle Devonian epibole

Exceptionally abundant specimens of Conularia aff. desiderata Hall occur in multiple marine obrution deposits, in a single sixth-order parasequence composed of argillaceous and silty very fine sandstone, in the Otsego Member of the Mount Marion Formation (Middle Devonian, Givetian) in eastern New York State, USA. Associated fossils consist mostly of rhynchonelliform brachiopods but also include bivalve molluscs, orthoconic nautiloids, linguliform brachiopods and gastropods. Many of the brachiopods, bivalve molluscs and conulariids have been buried in situ. Conulariids buried in situ are oriented with their aperture facing obliquely upward and with their long axis inclined at up to 87degree to bedding. Most specimens are solitary, but some occur in V-like pairs or in radial clusters consisting of three specimens, with the component specimens being about equally long or (less frequently) substantially different in length. The compacted apical end of Conularia buried in situ generally rests upon argillaceous sandstone. With one possible exception, none of the examined specimens terminates in a schott (apical wall), and internal schotts appear to be absent. The apical ends of specimens in V-like pairs and radial clusters show no direct evidence of interconnection of their periderms. The apical, middle or apertural region of some inclined specimens abuts or is in close lateral proximity to a recumbent conulariid or to one or more spiriferid brachiopods, some of which have been buried in their original life orientation. The azimuthal bearings of Conularia and nautiloid long axes and the directions in which conulariids open are nonrandom, with conulariids being preferentially aligned between 350 and 50degree and with their apertural end facing north-east, and nautiloids being preferentially aligned between 30 and 70degree. Otsego Member Conularia were erect or semi-erect, epifaunal or partially infaunal animals, the apical end of which rested upon very fine bottom sediment. The origin of V-like pairs and radial clusters remains enigmatic, but it is probable that production of schotts was not a regular feature of this animal's life history. Finally, conulariids and associated fauna were occasionally smothered by distal storm deposits, under the influence of relatively weak bottom currents. © The Palaeontological Association.

Variação espaço-temporal do zooplâncton no estuário do rio Quatipuru-Pará

A partir da hipótese de que a salinidade influencia fortemente a comunidade zooplanctônica, o objetivo deste trabalho é analisar a influência deste fator sobre essa comunidade no estuário do rio Quatipuru, Estado do Pará. Foram realizadas amostragens zooplanctônicas e de variáveis físicas e químicas da água ao longo do estuário, contemplando diferentes faixas de salinidade. As coletas foram realizadas em marés vazantes e enchentes. Os resultados mostraram que este estuário possui uma variação temporal de características física, química e biológica. A salinidade, em especial, sofreu variações decorrentes das mudanças de marés, bem como da variação sazonal da pluviosidade. A salinidade variou de 1,4 a 33,5 ups no período seco e de 0 a 17,9 ups no período chuvoso. Esta amplitude de salinidade possibilitou determinar para área diferentes condições hidrológicas (limnética, oligohalina, meso-polihalina e euhalina). Foram identificados 48 taxa, destacando os Copepoda como o grupo mais importante em termos quali-quantitativos, sendo adultos de Parvocalanus crassirostris, Pseudodiaptomus richardi, Acartia tonsa, Acartia lilljeborgi, Paracalanus quasimodo, Euterpina acutifrons e copepoditos os principais responsáveis pela sua dominância. Mollusca foi o segundo grupo dominante, onde véligeres de gastrópodes representaram 95% do total. A densidade total do zooplancton variou entre 993, 9 e 13254,7 Ind. m^-3 no verão e entre 944, 3 e 35908,8 Ind. m^-3 no inverno. As maiores abundância em maio e novembro foram em ocasião de maré vazante e enchente, respectivamente. Os baixos valores de diversidade e equitabilidade encontrados na faixa zero na condição de enchente mostram o predomínio de determinado grupo sobre os demais (larvas de Gastropoda). A maior diversidade e uniformidade da comunidade zooplanctônica ocorreram no verão. A comunidade zooplanctônica respondeu as variações de salinidade com espécies adaptadas aos maiores valores de salinidade na porção inferior do estuário, no verão, assim como espécies adaptadas as condições de mixohalinização na porção mais a montante, em maio. A maior abundância de copepoditos esteve associada negativamente com a salinidade, demonstrando que as espécies que estão recrutando os copepoditos são mais estuarinas verdadeiras do que costeiras. As análises de agrupamento e de componentes principais revelou grupos definidos, distribuídos em diferentes faixas de salinidade, este parâmetro sozinho explicou 56% (p=0,028) da variação da fauna no estuário do rio Quatipuru. A distribuição dos organismos, de uma maneira geral, esteve de acordo com a hipótese de que a salinidade influencia fortemente a comunidade zooplanctônica no sistema estuarino de Quatipuru - Pará.

Physa mezzalirai: um novo gastrópode da formação Adamantina (Bacia Bauru), Cretáceo Superior, São Paulo, Brasil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

IMPOSEX AS AN INDICATOR OF ORGANOTIN POLLUTION AT RIO DE JANEIRO SOUTH COAST: SEPETIBA AND ILHA GRANDE BAYS

Imposex is the development of male sexual characteristics, i.e., penis and/or vas deferens in females of dioecious gastropods. This phenomenon has been associated to the use of the organotin based marine antifouling paints and used worldwide as a bioindicator of pollution by the TBT (antifouling agent) as well as to evaluate the related ecological impact. This study reports imposex in Stramonita haemastoma at south coast of Rio de Janeiro State (Brazil), specifically at Sepetiba and Ilha Grande Bays. All the stations where snails were found have shown imposex. Ilha Grande Bay presented the highest values of imposex indices when compared to Sepetiba Bay. The results suggest that high concentration of shipping activities and coastal morphology are the principal causes at the most polluted sites.

Unusual anatomy of the ectoparasitic muricid Vitularia salebrosa (King and Broderip, 1832) (Neogastropoda: Muricidae) from the Pacific coast of Panama

The morphology and anatomy of Vitularia salebrosa, a muricid ectoparasitic on other mollusks, are investigated based on study of specimens from western Panama. Distinctive characters of this species include the small size of the buccal mass and radular apparatus, simplification of the odontophore muscles and diminished lateral teeth of the radula; all elongated, narrow proboscis; narrow digestive tract and a differentiable glandular region at the beginning of the posterior esophagus. These traits are consistent with adaptive specialization for an ectoparasitic life history.

New fossil pulmonate snails from the Paleocene of Itaborai Basin, Brazil (Pulmonata: Cerionidae, Strophocheilidae, Orthalicidae)

The limestones of ltaborai Basin (Middle Paleocene), Rio de Janeiro, Brazil, harbor a rich fossil fauna of pulmonate snails. Here two new pulmonate species are described: Brasilennea guttula sp. nov. (Cerionidae) and Eoborus rotundus sp. nov. (Strophocheilidae). B. guttula is the third species of its genus endemic from Itaborai, characterized mainly by its conspicuous shell shaped like a "water drop", with an acuminated spire. E. rotundus is the second of its genus from ltaborai, characterized mainly by its rounded outline and its relative small size. Moreover, a record of Plagiodontes aff. dental us (WOOD 1828) (Orthalicidae) is presented here for the first time for Itaborai Basin.

NEW FOSSIL RECORDS OF PLEISTOCENE MARINE MOLLUSKS IN SOUTHERN BRAZIL

Fossils of the gastropods Diodora patagonica, Zidona dufresnei, Olivancillaria carcellesi, Lamniconus lemniscatus carcellesi and the bivalve Arcinella brasiliana are registered for the first time from the outcrops of Chui Creek, on the coastal plain of Rio Grande do Sul State, southernmost Brazil, together with other taxa previously known elsewhere. The specimens were collected in a shallow Pleistocene marine facies exposed at the base of the banks of the creek, in a fossil concentration possibly formed by storm events. The taxa described here live in shallow environments (with the exception of A. brasiliana and Z. dufresnei) with sandy bottoms (except for D. patagonica, T patagonica, B. odites, C. rhizophorae and A. brasiliana). The presence of L. lemniscatus carcellesi, found living today only in Uruguay and Argentina, indicates a wider distribution for this taxon during the late Pleistocene.

Taxonomic study on the molluscs collected in Marion-Dufresne expedition (MD55) to SE Brazil: Xenophoridae, Cypraeoidea, mitriforms and Terebridae (Caenogastropoda)

The deep-water molluscs collected during the expedition MD55 off SE Brazil have been gradually studied in some previous papers. The present one is focused on samples belonging to caenogastropod taxa Xenophoridae Troschel, 1852, Cypraeoidea Rafinesque, 1815, mitriforms and Terebridae Morch, 1852. Regarding the Xenophoridae, Onustus aquitanus n. sp. is a new species, collected off the littoral of Espirito Santo and Rio de Janeiro, Brazil, 430-637 m depth (continental slope). The main characters of the species include the small size (c. 20 mm), the proportionally wide shell, the white colour, the short peripheral flange, the oblique riblets weakly developed and a brown multispiral protoconch. This appears to be the smallest living species of the family, resembling in this aspect fossil species. In respect to the Cypraeoidea, the following results were obtained: family Cypraeidae Rafinesque, 1815: Erosaria acicularis (Gmelin, 1791) and Luria cinerea (Gmelin, 1791) had the deepest record, respectively 607-620 m and 295-940 m, although the samples were all dead, eroded shells. Family Lamellariidae d'Orbigny, 1841: a total of three lots were collected, provisionally identified as Lamellaria spp. as the samples consist of only vestigial shells; possibly each lot represents a different species. Family Pediculariidae Gray, 1853: a sample of Pedicularia tibia Simone, 2005 was found, expanding the range c. 1000 km southwards, from Ceara to Espirito Santo. Family Ovulidae Fleming, 1822: Pseudosimnia lacrima n. sp., collected off Espirito Santo, 607-620 m depth, is described here and is mainly characterised by its strong biconic outline, small size (c. 7 mm), and a thick peripheral callus. Family Triviidae Troschel, 1863: Cleotrivia antillarum (Schilder, 1922) is recorded for the first time as deep as 620 m, and its distribution expanded from Rio Grande do Norte to Espirito Santo; Dolichupis akangus n. sp. with rounded outline and c. 15 transverse ribs; D. pingius n. sp. with the outer lip expanded posteriorly and c. 10 ribs. In respect to the mitriform neogastropods, the following species are emphasised: family Costellariidae MacDonald, 1860: Vexillum sp., 607-620 m depth; Turricostellaria amphissa n. sp., 295 m depth; T. jukyry n. sp.; T. apyrahi n. sp., both 790-1575 m depth; T. ovir n. sp., 1200 m depth; Nodicostellaria crassa (Simone, 1995), 240-600 m depth, with extension northwards of the range up to Espirito Santo; Austromitra decresca n. sp., 60-105 m depth. Family Mitridae Swainson, 1829: Subcancilla joapyra n. sp., 295 m depth; S. cf. straminea (Adams, 1853), 607-620 m depth. Family Volutomitridae Gray, 1854: Microvoluta corona n. sp., 1500-1575 m depth. Family Mitromorphidae Casey, 1904: Mitromorpha sama n. sp., 607-940 m depth; M. mirim n. sp., 60105 m depth. Regarding the conoidean Terebridae, this paper is a complement of a previous study. It deals with a new species Terebra assu Simone n. sp., from the Abrolhos Bank, 295 m depth, characterised by its narrow outline, yellowish colour, weak sculpture on the last whorls, and a proportionally broad, paucispiral protoconch. A second finding of Terebra alagoensis Lima, Tenorio & Barros, 2007 expands the geographic range from Alagoas to north Espirito Santo. A discussion on the systematics of the "complex Terebra doellojuradoi" in South American coast is also provided, highlighting the improbability of synonymy between T. leptapsis Simone, 1999 and T doellojuradoi Carcelles, 1953. Differences in size, sculpture, spire angulation, aperture, and mainly in protoconch, indicate specific separations. The presently studied terebrids belong to the "complex Terebra doellojuradoi", which encompasses closely related, deep-water, small species, possessing a relatively high degree of endemicity.

NEW RECORD OF CALYPTRAEID HOSTS FOR THE PEA CRAB CALYPTRAEOTHERES GARTHI (FENUCCI, 1975) (DECAPODA, PINNOTHERIDAE) IN ARGENTINA

Calyptraeotheres garthi (Fenucci, 1975) is one of nine species of Pinnotheridae occurring in Argentina and the only species of that genus located in this region. This species can be found from the San Maths Gulf, Argentina to Rio Grande do Sul, Brazil where it lives in symbiotic association with limpets of the family Calyptraeidae. Currently, two species of limpets have been reported as hosts of this species: Crepidula protea (d'Orbigny, 1841) and Crepidula argentina Simone, Pastorino & Penchaszadeh, 2000. We report here four more species of limpets serving as hosts of C. garthi, namely Bostrycapulus odites Collin, 2005, Crepidula cachimilla Cledon, Simone & Penchaszadeh, 2004, Crepidula plana Say, 1822 and Trochita pileus (Lamarck, 1822). Thus, this pinnotherid appears to be, as others members of the family, a generalist symbiotic species since it dwells on almost all the potential limpet species reported for Argentina. However, there are notable differences in prevalence of C. garthi on each host, which suggest that the symbiont might prefer species of Crepidula over the others genera (Trochita and Bostrycapulus). Additionally, there exists an apparent relationship between host size and prevalence (e.g., Crepidula cachimilla, the limpet with the highest prevalence, is clearly larger than the others hosts). Perhaps it is premature to conclude that the size of the host might be of benefit for the symbiont, but it is a hypothesis worthy of being explored.

Molluscicidal activity of some marine substances against the snail Biomphalaria glabrata (Mollusca, Planorbidae)

Freshwater snails of the genus Biomphalaria play a major role as intermediate hosts of Schistosoma mansoni, the etiologic agent of schistosomiasis. While Biomphalaria spp. control by molluscicides is one of the main strategies to reduce the snail population in infected areas, there are few effective molluscicides commercially available. Natural products may be considered as potentially useful and safe molluscicides. We have evaluated the molluscicidal activity of 12 extracts from ten marine organisms on adult and embryonic stages of Biomphalaria glabrata. Only extracts of the red algae Liagora farinosa and of the sponge Amphimedon viridis presented molluscicidal activity. Lethal concentration (LC)(50) values obtained were 120 mu g/mL for L. farinosa CH2Cl2 extract (apolar fraction) and 20 mu g/mL for A. viridis extract and halitoxin. The polar alga fraction and halitoxin had no effect on B. glabrata embryos. The algae apolar fraction was active on B. glabrata in all embryonic development stages, with LC50 values for blastulae at 42 mu g/mL, gastrulae at 124 mu g/mL, trochophore at 180 mu g/mL, and veliger at 222 mu g/mL. This is the first report of extracts from marine organisms which presented molluscicidal activity.

Das Hämocyanin zweier lebender Fossilien: Nautilus pompilius und Nucula nucleus

Als erste vollständige cDNA-Sequenz eines Muschel-Hämocyanins wurde das Nucula nucleus-Hämocyanin (NnH) sequenziert. Es besteht aus den beiden Isoformen NnH1 und NnH2, die eine Identität von etwa 61 % aufweisen. Beide sind aus acht funktionellen Domänen a-h aufgebaut, von denen die C-terminale Domäne h jeweils eine Extension von etwa 100 Aminosäuren besitzt. Auf Sequenzebene weist das Muschel-Hämocyanin eine eigentümliche Deletion im Bereich der ersten Kupferbindungsstelle und eine auffällig niedrige Anzahl an potentiellen N-Glykosylierungsstellen auf. Genomische Teilsequenzen bestätigen die Konservierung der Linkerintrons in Phase und Position, was bei den internen Introns nicht zu erkennen ist. Letztere konnten in den für die Domänen NnH1-d, NnH1-e und NnH2-c codierenden Genabschnitten nachgewiesen werden. Einen neuen Aspekt lieferte das interne Intron in NnH2-c, da es nur in einer der beiden Isoformen vorkommt. Das zweite sequenzierte Hämocyanin stammt von dem „lebenden Fossil“ Nautilus pompilius (NpH). Es wurde sowohl auf cDNA- als auch auf genomischer Ebene vollständig sequenziert und besteht aus sieben funktionellen Domänen, wobei die C-terminale Domäne h fehlt. Zu seinen Eigentümlichkeiten gehört neben 13 potentiellen N-Glykosylierungsstellen, von denen sich zwei innerhalb von Linkerregionen befinden, eine Deletion im Bereich der ersten Kupferbindungsstelle von NpH-g. Neben den konservierten Linkerintrons liegt ein Intron innerhalb des Signalpeptids sowie in den Genabschnitten für NpH-a und NpH-g. Dagegen ist weder zwischen dem Signalpeptid und NpH-a noch innerhalb der 3’UTR ein Intron vorhanden. Anhand der neuen Sequenzdaten wurde eine phylogenetische Analyse durchgeführt, in der sich die funktionellen Domänen von NnH als Schwestergruppe zu den korrespondierenden Domänen der Gastropoden anordnen. Den Erwartungen entsprechend stellt sich NpH basal innerhalb der Klasse der Cephalopoden. Phylogenetische Analysen mit der vollständigen Hämocyanin-Sequenz lösen die Verwandtschaftsverhältnisse der Klassen zueinander nicht auf, was auf schnelle Radiation schließen lässt. Die Gruppierungen innerhalb der Klassen werden dagegen sehr gut unterstützt. Mittels einer Distanzmatrix wurde eine molekulare Uhr berechnet, für deren Eichpunkt die Cephalopoden-Gastropoden-Aufspaltung vor 520 Millionen Jahren gewählt wurde. Die Entstehung der Acht-Domänen-Untereinheit fand danach vor 732 (± 33) Millionen Jahren statt. Die Trennung der Gastropoda und Protobranchia erfolgte vor 494 (± 50) Millionen Jahren, was mit Fossilfunden der Nuculidae aus dem Ordovicium übereinstimmt. Vor 396 (± 55) Millionen Jahren gingen aus einer Genduplikation die beiden Isoformen des Nucula nucleus-Hämocyanins hervor. Innerhalb der Cephalopoden wurde die Trennung zwischen Nautiloidea und Coleoidea auf 415 (± 24) Millionen Jahre zurückdatiert. Nach Fossildaten liegt der Trennungszeitraum der beiden Gruppen 470 - 400 Millionen Jahre zurück, was gut zu den Hämocyanin-Daten passt.

Differentielle Expression und molekulare Evolution von Mollusken-Hämocyanin

Molekularbiologische und biochemische Untersuchungen an den zwei Gastropoden-Arten Haliotis tuberculata und Haliotis asinina zeigten, dass diese jeweils zwei unterscheidbare Hämocyanin-Isoformen (HtH1/HaH1 und HtH2/HaH2) besitzen, die in unterschiedlichen Mengen in der Hämolymphe vorkommen. In situ-Hybridisierungsversuche an H. asinina ergaben, dass die beiden Hämocyanin-Isoformen sowohl entwicklungsspezifisch als auch gewebsspezifisch exprimiert werden. Die Transkription der Hämocyanin-Gene setzt bereits 9 Stunden nach der Befruchtung ein und ist von diesem Zeitpunkt an in allen Stadien der Larvalentwicklung nachweisbar. Während dieser Entwicklungsphase sind die Expressionsmuster der beiden Isoformen weitgehend überlappend, wohingegen in adulten Tieren in verschiedenen Geweben isoformspezifische Expressionsmuster auftreten. Diese Ergebnisse deuten auf funktionelle Unterschiede der beiden Hämocyanin-Isoformen hin, und somit darauf, dass Hämocyanin neben dem Transport von Sauerstoff noch weitere Funktionen ausüben könnte (Streit et al., 2005). Weiterhin wurden Untersuchungen zur Primär- und Sekundärstruktur der Hämocyanine aus H. tuberculata und zwei weiteren Arten (Megathura crenulata und Aplysia californica) durchgeführt. Von den Vetigastropoden M. crenulata und H. tuberculata konnten die für die beiden Hämocyanin-Isoformen kodierenden cDNA-Sequenzen vervollständigt werden. Von HtH1 und HtH2 wurden zudem die Gensequenzen komplettiert. Die Sequenzen des KLH1-Gens wurden bis auf 24 bp der 5’UTR und die für das Signalpeptid 1 kodierenden 33 bp ermittelt. Erstmals ist es gelungen, Promotorsequenzen von Mollusken-Hämocyanin-Genen zu sequenzieren. Für HtH2 wurden 181 bp und für KLH2 906 bp des Promotors analysiert. Beide Gensequenzen weisen das konservierte Sequenzmotiv der TATA-Box auf. Wie bei H. tuberculata treten auch bei M. crenulata die beiden Isoformen in unterschiedlichen Mengenverhältnissen in der Hämolymphe auf. In den bisher analysierten Sequenzen dieser beiden Gastropoden konnten keine regulatorischen Elemente identifiziert werden, welche die differentielle Expression bedingen könnten. Die Genstruktur des Hämocyanins von A. californica konnte ebenfalls aufgeklärt werden. Die kodierenden Bereiche des AcH-Gens werden durch insgesamt 45 interne Introns fragmentiert. Im Gen liegen neun Insertionspositionen vor, in denen paraloge Introns inserieren. Zudem sind neun Introns ortholog zu internen Introns anderer Mollusken-Hämocyanin-Gene. Im Fall der paralogen und orthologen Introns handelt es sich um sehr ursprüngliche Introns, die bereits vor der Radiation der Mollusken inserierten. Damit widerlegen diese Ergebnisse die bisherige Annahme („Intron late”-Hypothese), der zufolge die Insertion interner Introns erst nach der Trennung der Gastropoden und Cephalopoden eingesetzt haben soll. Im Zuge dieser Sequenzanalysen ergaben sich zudem Hinweise auf die Existenz einer weiteren AcH-Isoform, da 13 Fragmente ermittelt wurden, die in den kodierenden Bereichen Sequenzunterschiede von bis zu 20% zu AcH 1 aufweisen. Die detaillierten Studien der Haliotis-Hämocyanine deckten einen weitreichenden phylogenetischen Informationsgehalt der Hämocyanin-Sequenzen auf. In weiterführenden Analysen wurden Teilsequenzen der Hämocyanin-Gene von 12 verschiedenen Haliotis-Arten amplifiziert. Der daraus rekonstruierte Stammbaum liefert entsprechend spezifischer Indels eine deutliche Auftrennung der Haliotidae in eine nordpazifische und eine europäischaustralasische Abstammungslinie. Anhand dieser Analyse lassen sich der phylogeographische Ursprung der Haliotiden aufzeigen (Streit et al., 2006) und deren Wanderungsbewegungen nachvollziehen. Hämocyanin-Daten wurden des Weiteren für phylogenetische Analysen auf höherem taxonomischem Niveau eingesetzt. Innerhalb der Klasse der Polyplacophoren wurden interfamiliäre Verwandtschaftsverhältnisse rekonstruiert. Für diese Analyse wurden Teilsequenzen der Hämocyanin-Gene 17 unterschiedlicher Arten ermittelt. Die phylogenetische Untersuchung zeigt, dass sich die Polyplacophoren eindeutig in die beiden Ordnungen der Lepidopleurida und Chitonida auftrennen, da die Chitonida eine spezifische „Deletion” aufweisen. Anhand dieses Merkmals kann auch Callochiton bouveti, der diese „Deletion” besitzt und dessen phylogenetische Einordnung bisweilen umstritten war, eindeutig den Chitonida zugeordnet werden. Innerhalb der Chitonida bilden sowohl die Chitonina als auch die Acanthochitonina monophyletische Gruppen.

Foraminifera and microfossil occurence in Late Jurassic sediments of the North and South Atlantic

Biostratigraphical, taxonomical, and palaeocological results were obtained from Oxfordian to Tithonian foraminifers of the Northern and Southern Atlantic Ocean boreholes of the DSDP Legs 1, 11, 36, 41, 44, 50, and 79. An oversight on the cored Jurassic sections of the DSDP Legs 79 and the corresponding foraminiferal descriptions are given. The reddish brown, clayey and carbonaceous Cat Gap Formation (Oxfordian to Tithonian) of the Northern Atlantic Ocean, rich in radiolarians, yields less or more uniform, in most cases allochthonous foraminiferal faunas of Central European shelf character. No Callovian and Upper Tithonian foraminiferaI zones can be established. The zone of Pseudomarssonella durnortieri covers the Oxfordian/Kimmeridgian, the zone of Neobulimina atlantica the Kimmeridgian/Lower Tithonian interval. Characteristic foraminiferal faunas are missing since the Upper Tithonian to Valanginian for reason of a widely distributed regression which caused hiatuses observed all over the Northern Atlantic Ocean and in parts of Europe. The Upper Jurassic cannot be subdivided into single stages by foraminiferal biostratigraphy alone. The fovaminiferal zones established by Moullad (1984) covering a Callovian-Tithonian interval may be of some local importance in the Tethyan realm: It has too long-ranging foraminiferal species to be used as index marker in the word-wide DSDP boreholes. Some taxonomical confusion is caused because in former publications some foraminiferal species have got different names both in the Jurassic and Cretaceous. The foraminiferal biostratigraphy of drilled sections from DSDP boreholes is restricted by the drilling technique and for palaeo-oceanographical, biological, and geological reasons. Foraminiferal faunas from the DSDP originally described as ,,bathyal, or ,,abyssal,, have to be derived from shallower water. This contrasts the palaeo-water depths of 3000-4000 m which result from sedimentological and palaeo-geographical investigations.