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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A new look at members of the Superfamily Brachyopoidea Amphibia, Temnospondyli from the Early Triassic of Queensland and a preliminary analysis of brachyopoid relationships. In eryosuchids and mastodonsaur- this taxon. The anterior portion of the sphe- and bears lateral processes of c.
Plagiosauridae – Wikipedia
Judging from the size of the ornamented area of the tabular, the suture between that bone and the postparietal was evidently short. This outgrowth of the exoccipital subotic and a smaller lateral spindle Fig.
This was helrlung to support a relatively high degree of biological flexibility in these animals despite their somewhat unique ecology. The skull of G.
File:Gerrothorax – Wikimedia Commons
hellruny A—C, Gerrothorax pulcherrimus Fraas, The condition in Gerrothorax pulcherrimus is less certain: On the lingual surface of the mandible Figs 4A5B6B the dentary presents a smooth surface below the marginal tooth row. Generally, the paroccipital que, dorsolaterally directed suture Fig.
he,lrung Clearly, the posterior expansion of the orbits in Plagiosuchus pustuliferus has a profound effect on the pattern of skull roof bones. In SMNSthe lateral end of the right ventral blade. The anterior half of the floor of the adductor fossa is exposed in NHMS-WT and it can be seen that there is a thin, elongate ridge, formed by the angular, running parallel to the long axis of the mandible.
As is evident from the better preserved right palatal ramus, the flanges are orientated at near right-angles to each other. The structure, evolution and origin of the Amphibia. In Plagiosternum granulosumboth the prefrontal and the postfrontal are absent Warren, ; Gastou,contrasting with earlier interpretations which variously indicated the presence of one or both of these bones Fraas, ; von Huene, ; Nilsson, ; Romer, Acta Palaeontologica Polonica, 54, — In its portionally more widened than that of SMNS They helrlung a far distance poster- SMNSthe region of the paroccipital process and ior beyond the posterior margin of the dermal skull roof.
Like the maxillary teeth, the dentary teeth are of a simple conical shape, are subcircular in basal cross-section and possess simple infolding of the dentine; there is no evidence for carinae.
A, dorsal; B, lingual; C, labial; D, ventral views.
The ridge terminates anteriorly at the level of the Meckelian foramen posteriorly the floor of the adductor chamber was not preserved so the ridge may have extended further posteriorlyand is separated from the broken lingual wall of the adductor fossa by a groove several millimetres in width.
The paraquadrate tals bear a plate-like process with a finished bone surface foramen is visible on the ventral rim of the adductor submedullar ggerrothorax. With regard to the plagiosaurids known from Germany, Plagiosternum is known from one near-complete, albeit poorly preserved, skull Warren,one partial skull roof von Huene,and other fragmentary cranial and postcranial remains Fraas,; von Huene, ; Plagiosaurid is known from a partial skull and postcranial remains Jaekel, ; and Plagiosuchus is known from a poorly preserved skull hellrunh postcranial remains Fraas, ; von Huene, Hyperokynodon Tertrema Tertremoides Tirraturhinus.
Journal of Acta Zoologica Stockholm49, 1— Gerrothorax pulcherrimus from the ed. However, the alternative interpretation, that this element gerrothorxx either a postfrontal hellruny a postorbital, would be far more unusual in this respect.
In basal stereospondylomorphs, its the otics, which in turn are connected to the exoccipitals.
Chigutisaurus Compsocerops Koolasuchus Pelorocephalus Siderops. The plagiosaurid temnospondyl Plagiosuchus pustuliferus Amphibia: This high degree of palatoquadrate ossifica- terygoid conceals large parts of the otics Fig.
Transactions of the Royal chen, pp. Drawings of neurocranium and epipterygoid. In Gerrothorax, the high degree of ossification ossified palatoquadrates are present in finned tetra- of palatoquadrate and braincase see below is consistent podomorphs like Eusthenopteron Jarviksuggesting with the otherwise highly ossified skeleton — the limb that a high degree of palatoquadrate ossification might be girdles, vertebrae, the extensive cover by thick osteoderms plesiomorphic for tetrapods.
Dentary portion of a right mandible, in two fragments. Metoposauroidea Latiscopidae Almasaurus Latiscopus.
Posterolateral to the basal plate, the exoccipi- X Nervus vagusanalogous to the situation inferred in tals contact the pterygoids. This ventral blade probably contacted the dorsal surface This ossification is sheet-like, anteriorly flattened and of the basipterygoid ramus of the pterygoid, but this can- increasing in height posteriorly.
However, the possibility that the opening represents a natural vacuity cannot be discounted. An unambiguous stapes is present on both sides accommodates an anteroventral outgrowth of the otic in SMNS There is no trace of denticles or foramina on the body of the parasphenoid although, curiously, there is a weakly defined, raised central area with a pointed apex.
In Gerrothorax, Ghent Belgium. Elsewhere on the skull roof, the interconnected tubercles form prominent, elongate ridges, evident in particular on the jugals, parietals and postparietals.
Stratigraphically, the species ranges from the Grenzbonebed Oberer Muschelkalk, Ladinian to the overlying Lettenkeuper, where it has been recorded in three horizons Vitriolschiefer, Sandige Pflanzenschiefer, Untere Graue Mergel Hellrung, Comparative cranial osteology of Blanus Squamata: It is a robust element which may be subdivided into a tall, dorsal component and a ventral, condylar component.
The basipterygoid ramus, which medially contacts both the parasphenoid and the exoccipital, is rather long and forms a significant part of the posterior margin of the interpterygoid vacuity. In SMNSthe basal plate of the pa- transversely and forms the straight anterior margin of the rasphenoid is broad and short, with its widest portion basal plate.
The extensive ossification of both the two portions. What is evident, however, is that this region of the palate was exceptionally short cf.
Amphibian biology, volume 4: Cranial anatomy of the Permian temnospondyl amphibian Zatrachys serratus Copeand the phylogenetic position of the Zatracheidae. Micro-CT scans of posterior skull table with endocranial elements. No denti- men magnum is low and has a rounded dorsal edge owing cles are discernable on the parasphenoid of this specimen, to the inclination of the vertical column in a medial whereas in certain other specimens, like SMNS direction Fig.