Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "trilobite" wg kryterium: Temat


Wyświetlanie 1-3 z 3
Tytuł:
Ontogeny of a new cyrtosymboline trilobite from the Famennian of Morocco
Autorzy:
Loresey-Aubril, R
Feist, R.
Powiązania:
https://bibliotekanauki.pl/articles/20463.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
trilobite
cyrtosymboline trilobite
Famennian
Trilobita
ontogenesis
Proetoidea
Cyrtosymbolinae
protaspis
remains
Morocco
paleontology
Opis:
Abundant trilobite remains were recovered from late mid−Famennian marlstones from various sites in Eastern Tafilalet, southeast Morocco. All belong to a single taxon previously identified as Cyrtosymbole (Waribole) prima. This taxon is designated the type species of Osmolskabole gen. nov. A redefinition of this species, including the description of newly discovered, disarticulated exuviae both in limestone and silicified state of preservation, is given. In particular, silicified sclerites of various sizes allow the first complete growth series of a cyrtosymboline proetid to be presented. The close morphological resemblance of its protaspid stages to known proetoid larvae emphasizes the homogeneity of the early ontogeny in this superfamily. The Famennian proetoid anaprotaspis is also of comparable size to that of other Devonian proetoid larvae. However, their size−range is much less than that observed in Carboniferous larvae. This suggests that the survival of proetoid trilobites at the Frasnian−Famennian Kellwasser crisis did not result from a modification of the developmental strategy, as it might have been the case at the terminal Devonian extinction event. Moreover, O. prima possesses a plectrum from the metaprotaspid to the mid meraspid periods. This implies that the natant hypostomal condition is not steadily acquired early in the ontogeny of the Proetida. Thus we preclude the use of this character in the diagnosis of this order.
Źródło:
Acta Palaeontologica Polonica; 2005, 50, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trilobites from the latest Frasnian Kellwasser crisis in North Africa [Mrirt, Central Moroccan Meseta]
Autorzy:
Feist, R
Powiązania:
https://bibliotekanauki.pl/articles/20541.pdf
Data publikacji:
2002
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
trilobite
fauna
Frasnian
Trilobita
location
Kellwasser crisis
biogeography
Africa
Morocco
paleontology
Opis:
Latest Frasnian trilobites are recorded for the first time from North Africa. They occur in oxygenated limestones between the Lower and Upper Kellwasser horizons at Bou Ounabdou near Mrirt, central Moroccan Meseta. The faunas are very close to the contemporaneous associations in European sections both by their taxonomic composition and by patterns of evolutionary behavior towards eye reduction. Two new taxa are described: Gondwanaspis mrirtensis gen. et sp. nov., which is the last known representative of the Odontopleuridae before its extinction at the base of the Upper Kellwasser horizon, and Pteroparia ziegleri maroccanica subsp. nov., a geographical variant of the nominal subspecies from Sessacker in the Rhenish Slate Mountains.
Źródło:
Acta Palaeontologica Polonica; 2002, 47, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Red Devonian trilobites with green eyes from Morocco and the silicification of the trilobite exoskeleton
Autorzy:
Klug, C
Schulz, H.
De Baets, K.
Powiązania:
https://bibliotekanauki.pl/articles/22483.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
trilobite
silicification
diagenesis
Trilobita
Morocco
paleontology
mud mound
taphonomy
exoskeleton
transgression
Devonian
Opis:
Latest Emsian (Early Devonian) sediments at the famous mud−moundand trilobite−locality Hamar Laghdad (Tafilalt, Morocco) yielded some red−coloured remains of phacopid trilobites. Closer examination revealed that the eyes of these phacopids are often greenish in colour. EDX−analyses showed that the lenses retained their original calcitic composition, possibly greenish due to Feand Mn−impurities, while most of the exoskeleton was silicified. The silicified parts contain elevated concentrations of iron which causes the red colour. This phenomenon is explained by the porosity of the exoskeleton in contrast to the homogeneous and massive construction of the lenses and their Mg−content. These incompletely silicified trilobites enabled a reconstruction of the silicification process in trilobites. Their diagenetic alteration probably occurred as a result of events associated with the Cretaceous transgression.
Źródło:
Acta Palaeontologica Polonica; 2009, 54, 1; 117-123
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-3 z 3

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies