scholarly journals A new fossil piddock (Bivalvia: Pholadidae) may indicate estuarine to freshwater environments near Cretaceous amber-producing forests in Myanmar

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ivan N. Bolotov ◽  
Olga V. Aksenova ◽  
Ilya V. Vikhrev ◽  
Ekaterina S. Konopleva ◽  
Yulia E. Chapurina ◽  
...  
Keyword(s):  
High Abundance ◽  
Freshwater Species ◽  
Environmental Reconstruction ◽  
Freshwater Invertebrates ◽  
Stem Lineage ◽  
Freshwater Bivalves ◽  
Freshwater Environments

AbstractThe lower Cenomanian Kachin amber from Myanmar contains a species-rich assemblage with numerous plant and animal fossils. Terrestrial and, to a lesser degree, freshwater species predominate in this assemblage, while a few taxa with marine affinities were also discovered, e.g. isopods, ammonites, and piddocks. Here, we describe the Kachin amber piddock †Palaeolignopholas kachinensis gen. & sp. nov. It appears to be an ancestral stem lineage of the recent Lignopholas piddocks, which are estuarine to freshwater bivalves, boring into wood and mudstone rocks. Frequent occurrences and high abundance of †Palaeolignopholas borings and preserved shells in the Kachin amber could indicate that the resin-producing forest was partly situated near a downstream (estuarine to freshwater) section of a river. Multiple records of freshwater invertebrates (caddisflies, mayflies, stoneflies, odonates, and chironomids) in this amber could also manifest in favor of our paleo-environmental reconstruction, although a variety of local freshwater environments is known to occur in coastal settings.

scholarly journals Foram os Bivalves do Grupo Passa Dois (Exclusive Formação Rio do Rasto), Neopermiano, Invertebrados Tipicamente Dulcícolas?

2002 ◽  
Vol 29 (1) ◽  
pp. 83 ◽  
Author(s):  
RENATO PIRANI GHILARDI ◽  
MARCELLO GUIMARÃES SIMÕES
Keyword(s):  
Shell Morphology ◽  
Bivalve Mollusks ◽  
Late Permian ◽  
Freshwater Bivalve ◽  
Additional Tool ◽  
Intense Evaporation ◽  
Freshwater Bivalves ◽  
Freshwater Inputs ◽  
Freshwater Mollusks ◽  
Freshwater Environments

During the Late Permian Paraná Basin was a huge epeiric sea in which salinity deviated from either normal marine or freshwater, particularly in marginally environments. Sedimentological, geochemical, petrographic data and associated micro- and microflora have been used to identify such variations. Although shell morphology (paleoautoecology) and preservation (taphonomy) of bivalve mollusks could be used as an additional tool, these have been fully neglected. Previous authors based on the occurrence of charophyte oogonia in rocks of the Terezina/Corumbataí Formations (Passa Dois Group) and coeval occurrences outside the Brazilian portion of the basin, interpreted the fauna (Pinzonella illusa and Pinzonella neotropica assemblages) as typically freshwater. However, morphologic and taphonomic evidences do not corroborate this assumption: a- assimetrical sculptures and radial ornamentation found in shells of the genera Cowperesia and Ferrazia are absent in freshwater bivalve shells; b- anteriorly expanded shells (e.g., Runnegariella fragilis) are not present in mollusks that colonized freshwater environments, and c- lunule (e.g., Pinzonella, Itatamba, and Plesiocyprinella) is rare or absent in freshwater bivalves. Additionally, typical morphological features (e.g., claustrun, tubercles, shell torsion) exhibited by freshwater bivalves were not observed in the studied fauna. Assemblages including high proportion of shells with extensive solution pits concentrated in the umbonal region are common in bivalves that suffered prolonged exposures to freshwater conditions. These features have never been observed in the studied fossil record. Our data highly suggest that the reconstruction of Passa Dois Group paleosalinity must be done using a “myriad” of stratigraphic, sedimentologic, paleobiologic and taphonomic information. At this moment, we can only affirm that they were not typical freshwater mollusks. Probably, they lived in shallow water habitats, frequently affected by storms, and punctuated by episodes of intense evaporation and hypersalinity with influence of local freshwater inputs, configuring an situation of high environmental stress.

scholarly journals Whitemouth croaker, Micropogonias furnieri, trapped in a freshwater coastal lagoon: a natural comparison of freshwater and marine influences on otolith chemistry

2010 ◽  
Vol 8 (2) ◽  
pp. 311-320 ◽  
Author(s):  
Cristiano Q. de Albuquerque ◽  
Norbert Miekeley ◽  
José H. Muelbert
Keyword(s):  
Life History ◽  
Early Life History ◽  
First Year ◽  
Freshwater Species ◽  
Marine Life ◽  
Marine Population ◽  
Freshwater Population ◽  
Micropogonias Furnieri ◽  
First Year Of Life ◽  
Freshwater Environments

Strontium and barium incorporation into otoliths was compared between whitemouth croaker, Micropogonias furnieri, collected from an entrapped freshwater population (Mirim Lagoon) and a normal marine/estuarine population in southern Brazil. Chemical analysis was performed using LA-ICPMS with the objective of validating the effects of marine and freshwater environments on Sr and Ba incorporation as a basis for further investigation of marine and freshwater connectivity of M. furnieri. The freshwater population was dominated by older fish with mean ±SD age of 34±1 y, whereas the coastal samples were dominated by younger fish of 14±7 y. Comparison of strontium and barium incorporation among otolith life-history profiles indicated significantly higher barium and lower strontium for the freshwater population compared to the marine population. Furthermore, comparison of otolith material deposited in the freshwater, estuarine and marine life-history phases demonstrated clear differences among these environments. Mean concentrations of strontium and barium in otoliths of M. furnieri were respectively 710 and 112 µg g-1 for freshwater, 2069 and 16.7 µg g-1 for estuarine, and 2990 and 2.7 µg g-1 for marine life-history phases. Barium concentrations in otoliths from the freshwater population of M. furnieri appeared high relative to other freshwater species. Strontium levels across life-history profiles of marine fish increased with age from 2000 to 2900 µg g-1, possibly indicating more time spent in marine than estuarine waters with age. In contrast, for the freshwater population, strontium levels decreased during the first year of life approximately to 700 µg g-1, and remained low and stable thereafter, consistent with the early life-history occurring in an estuarine environment prior to entrapment in Mirim Lagoon. The results confirm the strong and opposite effects of marine and freshwater environments on incorporation of barium and strontium into otoliths, and indicate that the population of M. furnieri in Mirim Lagoon represents an isolated population that does not reproduce and is therefore likely to become extinct.

scholarly journals Flatfishes colonised freshwater environments by acquisition of various DHA biosynthetic pathways

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Yoshiyuki Matsushita ◽  
Kaho Miyoshi ◽  
Naoki Kabeya ◽  
Shuwa Sanada ◽  
Ryosuke Yazawa ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Docosahexaenoic Acid ◽  
Fatty Acid Metabolism ◽  
Acid Metabolism ◽  
Marine Fishes ◽  
Freshwater Species ◽  
Biosynthetic Pathways ◽  
Marine Environments ◽  
Functional Combination ◽  
Freshwater Environments

AbstractThe colonisation of freshwater environments by marine fishes has historically been considered a result of adaptation to low osmolality. However, most marine fishes cannot synthesise the physiologically indispensable fatty acid, docosahexaenoic acid (DHA), due to incomplete DHA biosynthetic pathways, which must be adapted to survive in freshwater environments where DHA is poor relative to marine environments. By analysing DHA biosynthetic pathways of one marine and three freshwater-dependent species from the flatfish family Achiridae, we revealed that functions of fatty acid metabolising enzymes have uniquely and independently evolved by multi-functionalisation or neofunctionalisation in each freshwater species, such that every functional combination of the enzymes has converged to generate complete and functional DHA biosynthetic pathways. Our results demonstrate the elaborate patchwork of fatty acid metabolism and the importance of acquiring DHA biosynthetic function in order for fish to cross the nutritional barrier at the mouth of rivers and colonise freshwater environments.

Stabilizing pyritic material

1989 ◽  
Vol 4 ◽  
pp. 244-248 ◽  
Author(s):  
Donald L. Wolberg
Keyword(s):  
Significant Contribution ◽  
Organic Materials ◽  
Sedimentary Rocks ◽  
Iron Sulfides ◽  
Decomposition Products ◽  
Iron Minerals ◽  
Pyrite Formation ◽  
Organic Sediments ◽  
Freshwater Environments

The minerals pyrite and marcasite (broadly termed pyritic minerals) are iron sulfides that are common if not ubiquitous in sedimentary rocks, especially in association with organic materials (Berner, 1970). In most marine sedimentary associations, pyrite and marcasite are associated with organic sediments rich in dissolved sulfate and iron minerals. Because of the rapid consumption of sulfate in freshwater environments, however, pyrite formation is more restricted in nonmarine sediments (Berner, 1983). The origin of the sulfur in nonmarine environments must lie within pre-existing rocks or volcanic detritus; a relatively small, but significant contribution may derive from plant and animal decomposition products.

KOMPOSISI JENIS DAN KELIMPAHAN IKAN DI PERAIRAN TELUK DORERI, MANOKWARI

2008 ◽  
Vol 6 (1) ◽  
Author(s):  
Maria Massora
Keyword(s):  
Fish Species ◽  
Economic Value ◽  
High Abundance ◽  
Abundance Index

<em>A study was done to search the composition and abundance of fish species in the waters of the Doreri Gulf the District of Manokwari, from September - October 2005.  The fish catchments wash about 143 specimens consist of 49 species included in 23 families.  The species of fish with a high abundance index consists of Nemipterus celebicus, Upeneus sundaicus, and Upeneus sulphureus.  Those fishes have a high economic value in the market of Manokwari</em>

Sign in / Sign up

Export Citation Format

Share Document