Grès à Voltzia

2012 ◽  
pp. 123-132
Keyword(s):  
Grès À Voltzia

The oldest Diptera (Insecta) from the Upper Buntsandstein (early Middle Triassic) of Europe

Zootaxa ◽  
2021 ◽  
Vol 5067 (1) ◽  
pp. 135-143
Author(s):  
ELENA D. LUKASHEVICH
Keyword(s):  
Fossil Record ◽  
New Genus ◽  
Middle Triassic ◽  
Insect Fauna ◽  
The Family ◽  
Lower Franconia ◽  
Grès À Voltzia ◽  
Early Middle Triassic

The fossil record of Triassic Diptera is still poor, with the oldest dipteran assemblage described from the Upper Buntsandstein of the ‘Grès à Voltzia’ Formation (early Anisian, France). From the stratigraphically closest insect fauna of the Röt Formation of Lower Franconia, Germany, the first Diptera, Bashkonia franconica gen. et sp. nov. is described based on an isolated wing. The new genus is assigned to the family Nadipteridae, bridging the gap between two other genera included.  

New grylloblattid insects (Insecta: Grylloblattida) from the Grès à Voltzia of the Vosges (Middle Triassic of France)

2011 ◽  
Vol 45 (2) ◽  
pp. 159-166 ◽  
Author(s):  
D. S. Aristov ◽  
L. Grauvogel-Stamm ◽  
F. Marchal-Papier
Keyword(s):  
Middle Triassic ◽  
Grès À Voltzia

Decay and preservation of polychaetes: taphonomic thresholds in soft-bodied organisms

Paleobiology ◽  
1993 ◽  
Vol 19 (1) ◽  
pp. 107-135 ◽  
Author(s):  
Derek E. G. Briggs ◽  
Amanda J. Kear
Keyword(s):  
Chemical Composition ◽  
Soft Tissues ◽  
Lipid Fraction ◽  
Relative Proportion ◽  
Two Dimensions ◽  
The Body ◽  
Whole Body ◽  
Fluid Loss ◽  
Preservation Potential ◽  
Grès À Voltzia

A series of experiments was carried out to investigate the nature and controls (oxygen, microbial populations, agitation) on the degradation of soft tissues. Decay was monitored in terms of morphological change, weight loss, and change in chemical composition in the polychaete Nereis virens. Polychaetes include a range of tissue types of differing chemical composition and preservation potential: muscle, cuticle, setae, and jaws. Regardless of conditions, all the muscle had broken down and fluid loss through the ruptured cuticle had reduced the carcass to two dimensions within 8 days at 20°C. In most cases some cuticle, in addition to the jaws and setae, remained after 30 days. Where oxygen was completely eliminated, the rate of decay of the more volatile issues was significantly reduced. The degree of both osmotic uptake of water by the carcass and changes in water pH differed depending on whether the system was open or closed to oxygen diffusion. Autolytic and chemical processes are not sufficient to fully degrade the carcass in the absence of bacteria. Where internal bacteria are present, the presence or absence of water column bacteria made little difference to decay rate. Initial degradation (in the first 3 days) affects mainly the lipid fraction and the collagen of the cuticle. Later decay reduces the nonsoluble protein and increases the relative proportion of refractory structural components (tanned chitin and collagen) to more than 95% by day 30. Thus, only the sclerotized tissues are likely to survive beyond 30 days in the absence of early diagenetic mineralization. The sequence of degradation predicted from the relative decay resistance of macromolecules in the sedimentary record (protein → carbohydrate → lipid) is not, therefore, a consistent indicator of the preservation potential of structural tissues which incorporate them.The experiments reveal five stages in the decay of polychaete carcasses; whole/shriveled, flaccid, unsupported gut, cuticle sac, jaws and setae. All are represented in the fossil record. This allows an estimation of how far decay proceeded before it was halted by the fossilization process. The most complete preservations occur in the Cambrian where the Burgess Shale preserves evidence of muscle tissues. Traces of the gut and cuticle are more widely preserved, as at Mazon Creek, Grès à Voltzia, Solnhofen, and Hakel. Preservation varies within Konservat-Lagerstätten. The most common whole body preservation includes only the more recalcitrant tissues, jaws (where present) and setae, with an impression of the body outline. The stage of decay can be used as a taphonomic threshold, to provide an indication of how significantly the diversity of an exceptionally preserved biota is likely to have been reduced by taphonomic loss.

A new mayfly species Triassodotes rasnitsyni sp. nov. of the family Misthodotidae Tillyard, 1932 (Insecta; Ephemerida, Permoplectoptera) from the Triassic deposits of Kuzbass, Russia

2021 ◽  
Vol 4 (5) ◽  
Author(s):  
NINA D. SINITSHENKOVA
Keyword(s):  
North America ◽  
Middle Triassic ◽  
Sister Group ◽  
Upper Permian ◽  
Early Permian ◽  
The Urals ◽  
The Family ◽  
Grès À Voltzia ◽  
Perm Region ◽  
Group Family

The mayfly sister group family Misthodotidae Tillyard, 1932 includes two genera: Misthodotes Sellards, 1909 and Triassodotes Sinitshenkova & Papier, 2005. Misthodotes species have so far been known only from the Permian, six Early Permian species have been described from North America (Carpenter, 1933, 1979; Tillyard, 1932, 1936), one from Germany (Kinzelbach & Lutz, 1984) and two from the Perm region of Russia (Tshernova, 1965). Only three species are known from the Upper Permian deposits: two from the famous Isady locality in the Vologda Region of Russia (Sinitshenkova, 2013; Sinitshenkova & Vassilenko, 2012) and one from the Urals (Novokshonov et al., 2002). The only Triassodotes species was found in the Middle Triassic Grès à Voltzia deposits in France (Sinitshenkova et al., 2005).

Sign in / Sign up

Export Citation Format

Share Document