Temat: anuran - Prolib Integro

Skocz do pozycji: 1.

Tytuł:: Strange tadpoles from the lower Miocene of Turkey: Is paedogenesis possible in anurans?
Autorzy:: Dubois, A.
Grosjean, S.
Paicheler, J-C.
Tematy:: tadpole
Lower Miocene
Miocene
Turkey
paleontology
pedogenesis
anuran
Amphibia
Anura
egg
fossil; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Powiązania:: https://bibliotekanauki.pl/articles/21427.pdf Link otwiera się w nowym oknie
Opis:: Fossil material from the lower Miocene collected in the basin lake of Beşkonak (Turkey) included 19 slabs showing 19 amphibian anuran tadpoles of rather large size, at Gosner stages 36–38. These well preserved specimens show many morphological and skeletal characters. They are here tentatively referred to the genus Pelobates. Two of these tadpoles show an unusual group of black roundish spots in the abdominal region, and a third similar group of spots is present in another slab but we were unable to state if it was associated with a tadpole or not. Several hypotheses can be proposed to account for these structures: artefacts; intestinal content (seeds; inert, bacterial or fungal aggregations; eggs); internal or external parasites; diseases; eggs produced by the tadpole. The latter hypothesis is discussed in detail and is shown to be unlikely for several reasons. However, in the improbable case where these spots would correspond to eggs, this would be the first reported case of natural paedogenesis in anurans, a phenomenon which has been so far considered impossible mostly for anatomical reasons (e.g., absence of space in the abdominal cavity).
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Larval development in Oligocene palaeobatrachid frogs
Autorzy:: Rocek, Z
Tematy:: anuran fauna
palaeobatrachid frog
Czech Republic
frog
Palaeobatrachidae
Anura
Oligocene
larval development
larva
paleontology; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Powiązania:: https://bibliotekanauki.pl/articles/21425.pdf Link otwiera się w nowym oknie
Opis:: A detailed account of the development of skeletal and some soft−tissue structures is based on 171 fossil tadpoles and metamorphosing froglets of Palaeobatrachus sp. from the Late Oligocene of the Czech Republic (locality Bechlejovice). Their exceptionally good preservation resulted from fossilization in diatomites. The fossil developmental series was compared with normal development of the contemporary anuran Xenopus laevis (Pipidae) represented by cleared and stained (alizarin/toluidin−blue) whole−mount specimens. The comparison revealed that in spite of differences in the sequence of ossification and its timing (e.g., ossification of the otic capsules and ribs was retarded in Xenopus whereas dermal ossification was retarded in Palaeobatrachus), in the number of free ribs, and in composition of the sacral region (the synsacrum in Palaeobatrachus involves two posterior presacrals, whereas there is a single sacral in Xenopus), both genera were similar in great number of anatomical features that appear during development. The most important difference is the shape of vertebral centrum (procoelous in Palaeobatrachus, opisthocoelous in all Pipidae) which is formed in comparatively early developmental stages. A view that could result from anatomical comparisons is that Palaeobatrachus could be derived from the Pipidae, but this is doubtful due to biostratigraphic and palaeogeographic discrepancies. The earliest palaeobatrachids were recorded from the Late Cretaceous of Europe but pipids could not invade northern continents after the Early Cretaceous when the Tethys Sea prevented interchanges of anuran faunas. Also, all palaeobatrachids retain primitive anatomical features (e.g., five pairs of ribs) that were more derived even in the earliest pipids from the Lower Cretaceous of Israel.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 3.

Tytuł:: A review of Neusibatrachus wilferti, an Early Cretaceous frog from the Montsec Range, Northeastern Spain
Autorzy:: Baez, A M
Sanchiz, B.
Tematy:: Cretaceous
Lleida Province
Amphibia
frog
anuran
Palaeobatrachidae
Anura
skeleton
Neusibatrachus wilferti
Spain
paleontology
Pipoidea; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Powiązania:: https://bibliotekanauki.pl/articles/21953.pdf Link otwiera się w nowym oknie
Opis:: Neusibatrachus wilferti is an anuran from the late Berriasian–early Valanginian fossiliferous lacustrine limestones that are exposed in the eastern part of the Montsec Range, province of Lleida, Spain. It was originally described by Seiffert in 1972 and its phylogenetic position has since been discussed. Neusibatrachus has been considered an undeterminable fossil, an abnormal individual, or a primitive palaeobatrachid. Here we redescribe the only available specimen, and clarify features, such as absence of palatines, nine presacrals, and procoelous vertebral centra, that have been the subject of previous debates. We consider the specimen to be a postmetamorphic individual and make developmental interpretations of some of its characters. In particular, we provide evidence of a living anuran (Rana iberica) that resembles Neusibatrachus in the development of intervertebral articulations. Neusibatrachus is considered a valid genus, which differs from other anurans, except for the pipoids, in the joint presence of an azygous frontoparietal and a parasphenoid lacking the subotic alae, although it differs from the pipoids in having nine presacral vertebrae. Morphological evidence indicates that Neusibatrachus is related to Xenoanura, the pipoid branch in the living Amphibia Tree of Life based on molecular data. Moreover, it might be a member of the pipoid clade proper, which presently includes the Pipidae, Rhinophrynidae, and several fossil taxa, including the Palaeobatrachidae, although the evidence is not conclusive.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: New frogs from the latest Cretaceous of Hateg Basin, Romania
Autorzy:: Venczel, M
Csiki, Z.
Tematy:: terrestrial microvertebrate
aquatic microvertebrate
Romania
Cretaceous
fluvio-lacustrine deposit
anuran
Amphibia
frog
Anura
Hateg Basin
Maastrichtian
paleontology; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Powiązania:: https://bibliotekanauki.pl/articles/22784.pdf Link otwiera się w nowym oknie
Opis:: The latest Cretaceous (Maastrichtian) fluvio−lacustrine deposits of Haţeg Basin (Romania) have yielded a number of aquatic and terrestrial microvertebrates, including dissociated skeletal remains of the following anuran taxa: Hatzegobatrachus grigorescui gen. et sp. nov., Paralatonia transylvanica gen. et sp. nov., andAnura indet. H. grigorescui sp. nov. (type species), retaining some leiopelmatid−grade anuran features, is diagnosed as a small−sized primitive frog with still unclear relationships. P. transylvanica sp. nov. (type species) is a middle−sized discoglossine frog. Based on the characters of jaw−bones andpost−cranial skeletal elements, it appears as intermediate between primitive (Eodiscoglossus−like) andmore derived (Latonia−like) discoglossine discoglossid. In Hatzegobatrachus and Paralatonia the morphology of the hipbones shows that they differ in saltatorial abilities. Consequently, these forms may have occupied distinct ecological niches, suggesting that the latest Cretaceous microvertebrate assemblages of Haţeg Basin were connectedto more complex ecosystems than considered before.
Dostawca treści:: Biblioteka Nauki

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