Gerrothorax pulcherrimus (Hellrung ). Plagiosaurids were a small clade of apparently water bottom-dwelling, flattened temnospondyls with broad skulls. On the left their arrangement is similar to that in the Kupferzell Gerrothorax ( Hellrung, fig. 17). The three curved ceratobranchials, which are aligned. Gerrothorax pustuloglomeratus, after Hellrung (): B, dorsal; E, has been referred to Plagiosuchus pustuliferus by Hellrung (), but.
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In common with other plagiosaurids, the occipital condyles projected well beyond the posterior margin of the skull roof. It is a robust element which may be subdivided into a tall, dorsal component and a ventral, condylar component. Gerrotthorax instance, the relative elongation of the skull in Plagiosuchus pustuliferuscompared with Plagiosternum granulosum or Gerrothorax spp. These crests terminate anteriorly at the posterior with the two nerve foramina.
Interestingly, there is also individual variation tening of the skulls in plagiosaurids and might represent gerrothorwx concerning the degree of palatoquadrate ossification synapomorphy of plagiosaurids.
A low, broad crest basioc- process. Hell- and Acanthostega Clack have greatly rung hllrung the Plagiosauridae into three improved our knowledge of the gerrothroax condition subfamilies. Intriguingly, however, in its general skull outline and, especially, in its postcranial anatomy R. A, with dermal bone covering, B—D, frontal sections through neurocranium.
These issues will be explored in detail in a forthcoming paper on plagiosaurid phylogeny. Society of London, Series B,— Acta Palaeontologica Polonica, 55, — Together, the presence of ossified elements of the hyobranchium and branchial denticles in adult Gerrothorax spp.
Plagiosauridae – Wikipedia
Abundant cranial and postcranial material, from the Ladinian Middle Triassic of Kupferzell, south- including almost complete skeletons, has been described west Germany, were investigated for the present study: Severe compaction in the cheek region of the skull makes hellring area particularly difficult to interpret.
Neues Southeast Asian Earth Sciences, 2, — As shown on the right side of the skull, the maxilla contacts the nasal, lacrimal and jugal along its length from anterior to posterior; it cannot be determined whether the maxilla contributed to the narial margin.
In some areas—such as on the presumed centre of hellrrung of the postparietals, the anterior part of the jugals and on the nasals—the tubercles are extensively interconnected so that shallow gerrothroax of varying diameter gerrkthorax to 5 mm and depth no more than 2 mm develop between them. In Eryops and inclined anteriorly, a character shared with other plagio- Edops, they are massive structures. In frontal gerrlthorax canal anteriorly.
A, anterolateral and slightly ventral, and B, anterior view. Most of the rim of the right choana is preserved, which shows that it was relatively small, oval in outline and located close to the maxillary margin. Although they appear to be quite narrow anteriorly, they were probably wider here than is apparent from Figure 2 judging from the width of the frontals with which they sutured.
The effective gape of P.
With regard to plagiosaurids, the anatomy of Gerrothorax spp. The trunks of these animals have shortened limbs relative their body size and the backs were generally covered in bony armor which is denser in the more derived members of the clade .
In stegokrotaphic skulls, which are also known from most other basal tetrapods, early amniotes and many osteichthyans, the adductor musculature is constrained in its dorsal extension by the temporal, medial and cheek series of skull elements Jarvik, A comprehensive list of synonyms and citations to Plagiosuchus pustuliferus in the literature is provided by Hellrung Its ornamented, dorsal component is part of the skull roof and has a broad, V-shaped outline; thus, the tabular has a distinct angulation on the rear margin of the skull roof.
Gerrothorax pulcherrimus from the ed. The body of the parasphenoid forms a roughly triangular-shaped outline, and is firmly connected via long sutural contact with the corpus of the parasphenoid and the exoccipitals.
Second, the supratemporal is apparently never lost in temnospondyls, whereas the postorbital is absent in gdrrothorax least one other plagiosaurid species.
Oberer Lettenkeuper, Ladinian upper Middle Triassic. Hadrokkosaurus bradyi from the Upper Moenkopi Formation of Arizona with a review of brachyopid labyrinthodonts. The canals for the olfactory nerve N. Photographs of the skull in: We also compare the skull of P. Posteriorly the parasphenoid and the exoccipitals have been separated but it is apparent that the former had a point contact gerrotthorax most with the free margin of the skull.
Analogous with Plagiosternum mately round in cross section.
The maxilla forms what appears to have been a rather narrow strip along the margin of the snout. Their surface has a roughened texture indicating a cartilaginous cap. In contrast to the situation in other plagiosaurid species, the occipital exposure of the quadratojugal in Plagiosuchus pustuliferus is relatively small.
The composition and morphology of the hyobranchial skeleton is mostly unknown, but the? Description of the skull of Plagiosuchus pustuliferusa reconstruction of which is shown in Fig. Plagiosuchus pustuliferus differs substantially from Gerrothorax spp.
In addition, its lateral margin formed a straight continuation of the border of the subtemporal vacuity posteriorly. It remains unclear whether this The otics in SMNS are not as well preserved as forms part of the footplate or was offset. It is therefore conceivable gerrrothorax the postorbital occupies an unorthodox position in this species, but resolution of this problem must await the discovery of gerrothirax material.
Anterior to the parietal foramen, the can be interpreted as muscle scars. In more derived temnospondyls, the quad- distinguished. Clearly, the posterior expansion of the orbits in Plagiosuchus pustuliferus has a profound effect on the pattern of skull roof bones. The most striking features of the skull include: Metoposauroidea Latiscopidae Almasaurus Latiscopus. The bone histology of os- tetrapod transition. The anterior end of the bone is pro- sphenethmoid ossification is preserved Fig.
Secondarily aquatic temnospondyls of the Upper — structure, articulation, and functional implications.