Search results for "Skull roof"
showing 5 items of 5 documents
Cranial suture biomechanics inMetoposaurus krasiejowensis(Temnospondyli, Stereospondyli) from the upper Triassic of Poland
2019
Cranial sutures connect adjacent bones of the skull and play an important role in the absorption of stresses that may occur during different activities. The Late Triassic temnospondyl amphibian Metoposaurus krasiejowensis has been extensively studied over the years in terms of skull biomechanics, but without a detailed description of the function of cranial sutures. In the present study, 34 thin sections of cranial sutures were examined in order to determine their histovariability and interpret their biomechanical role in the skull. The histological model was compared with three-dimensional-finite element analysis (FEA) simulations of the skull under bilateral and lateral biting as well as …
The temnospondyl amphibian Cyclotosaurus from the Upper Triassic of Poland
2005
A gap in the Late Triassic fossil record of the capitosaur amphibian Cyclotosaurus is filled by new material from lacustrine deposits at Krasiejow, Poland, corresponding in age to the Lehrberg Beds (late Carnian) of Germany. The skull of the Polish cyclotosaur is intermediate in several respects between that of Cyclotosaurus robustus from the middle Carnian Schilfsandstein of Germany and the younger C. mordax from the early Norian Stubensandstein. It shows a decrease in the width of the skull and in the degree of con- cavity of the posterior margin of the skull roof. The differ- ences are significant enough to warrant erection of a novel species, the name Cyclotosaurus intermedius sp. nov. …
Ein neues captorhinomorphes reptil aus dem thüringischen rotliegend (Unter-Perm; Ost-Deutschland)
1991
Thuringothyris mahlendorffae n.gen. n.sp. is described on the basis of the skull roof, palate, stapes and much of the postcranial skeleton from the Upper Rotliegend (Tambach-Schichten) of the Thuringian Forest in eastern Germany. The new taxon shows both protorothyridid and some captorhinid features. The interrelationships of the »Protorothyrididae«, primitive Captorhinidae, and earliest Diapsida are reviewd. The tetrapod material is used to reassess the biostratigraphic position of the fossil-bearing horizon.
Morphology and function of the sutures in the dermal skull roof of Discosauriscus austriacus Makowsky; 1876 (Seymouriamorpha; Lower Permian of Moravi…
1995
Abstract Sutural patterns in the dermal skull roof were among others studied in Discosauriscus austriacus (Seymouriamorpha) and Onchiodon labyrinthicus (Temnospondyli). Main sutural structures are defined as lamellae; shelves; vertical walls; and grooves. These types have different functional manifestations. The basic pattern is described for Discosauriscus austriacus. Similarities of patterns in taxa not closely related are most likely a result of convergence. Intraspecific variability is generally low but can be observed during ontogeny. The patterns of subjacent areas in Eusthenopteron foordi (Osteolepiformes) are very similar to Discosauriscus austriacus. It is shown that sutural morpho…
Über die Micromelerpetontidae (Amphibia: Temnospondyli). 1. Morphologie und Paläoökologie desMicromelerpeton credneri (Unter-Perm; SW-Deutschland)
1995
This paper presents a redescription of the most important features of the skull roof, palate, hyobranchial apparatus, and the postcranial skeleton ofMicromelerpeton credneri. It is possible to distinguish a temporal sequence of three morphotypes that can be differentiated by size and slight differences in the structure of the skull roof. They led a predaceous existence in the pelagial of three fairly deep lakes that had excellent potential for the preservation of fossils. Comparisons of the size-frequency distributions for specimens from different horizons indicate facultative paedomorphosis by means of progenesis. This phenomenon may be related to different trophic strategies and possible …