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.
|Published (Last):||11 October 2009|
|PDF File Size:||14.47 Mb|
|ePub File Size:||18.6 Mb|
|Price:||Free* [*Free Regsitration Required]|
It is therefore conceivable that the postorbital occupies an unorthodox position in this species, but resolution of this problem must await the discovery of additional material. The basisphenoid region is bilater- enoid region and parasphenoid Fig. The ornamentation is in the form of bulbous, irregular tubercles of varying height up to c.
Posterior to the large foramen for ramus of pterygoid. They extend a far distance poster- SMNSthe region of the paroccipital process and ior beyond the posterior margin of the dermal skull roof. Unusually, however, it also forms most of the skull margin, broadly separating the maxilla anteriorly from the quadratojugal posteriorly. C, dorsal; F, ventral views. Posteriorly, it is co- blade is directed increasingly posteroventrally and its size ossified with the otics, and posteromedially probably with decreases, so that this portion is slender and approxi- the basisphenoid region.
However, in NHMS-WT only the medial fossa appears to be formed by the articular, whereas the lateral fossa appears to continuous with the labial mandibular wall, which is formed by the surangular.
The suspensorial region on the right side of the skull has also been pushed forward significantly. The first one is very low and located pos- of the lateral wings and is framed by ventral crests later- teroventral to the above-mentioned ventrolateral fossa ally. Gerrothorax pustuloglomeratusafter Hellrung Despite its unique morphology flattening of skull and body, extensive bony armour, etc.
The dentition is feebly developed on both skull and mandible. The shaft is thin in cross section, rather plate-like than rounded. Secondarily aquatic temnospondyls of the Upper — structure, articulation, and functional implications. The large foramen for the processes contact the dermal skull roof throughout their optic nerve N. In other temnospondyls, muscle scars are also found on the internal surface of the postorbital, postfrontal and supratemporal gerrothorzx.
The exception is SMNSan articulated skeleton minus the skull, which preserves the remains of a number of elongated up to 6 cm in lengthgently curved, rod-like elements attached to the anterior hellrnug of the dorsal clavicular process sensu Pawley, of the left clavicle.
First, the sutural contacts are most consistent with identification as a supratemporal: The exceptionally short maxilla is the main tooth-bearing element. In contrast wings, a small foramen of uncertain affinity is situated on to the latter specimen, however, the laterosphenoid wall is either side of the bone Fig.
The parietals are robust, distinctly L-shaped elements. Surrey Beatty, Chipping Norton, pp.
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. In transverse sections, the canals for the and is ventrally co-ossified with these elements internal carotid arteries are well visible gerrrothorax basisph- Figs 5C—D, gedrothorax. However, the laterosphenoid the degree of ossification has little phylogenetic signifi- region is unossified or absent in stereospondyls and their cance, similar to the extent of palatoquadrate ossification stem-forms Schoch and Milner Neues Southeast Asian Earth Sciences, 2, — Interpretive drawing of the skull in ventral view, with bones indicated on the lower figure.
In the anterome- and ventrally and by the exoccipitals posteriorly, the dial part of the basisphenoid region, there is a conspic- otics laterally and the sphenethmoid region anteriorly. The descending, or occipital, flange of the squamosal is an unornamented, relatively deep lamina of bone. Journal of Acta Zoologica Stockholm49, 1— However, on the left side of the skull this pattern is not repeated: Canadian Journal of Earth Sciences, 40, — burgh: Hellrunt epipterygoid and neurocranium of G.
Lower jaws, lower tetrapods: This filled by cartilage and housed the inner hlelrung Fig.