Enaliosuchus macrospondylus (Crocodylia, Metriorhynchidae) du Valanginien de Barret-le-Bas (Hautes Alpes, France): Un cas unique de remontée des narines externes parmi les crocodiliens

Hua, Stéphane; Vignaud, Patrick; Atrops, François; Clément, Arnaud

doi:10.1016/s0016-6995(00)80080-7

Cited by 26 publications

(30 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The divided external nares is hypothesized to be an adaptation for more efficient respiratory airflow [20], while the posterodorsal retraction of the external nares is observed in clades with sustained swimmers (e.g. ichthyosaurs and cetaceans; see [82] and references therein).…”

Section: Discussionmentioning

confidence: 99%

“…However, Tithonian specimens of Cricosaurus saltillense [21] and Cricosaurus sp. [19], and the Valanginian species Cricosaurus macrospondylus [20], had carinated and more vertically orientated dentition. In most rhacheosaurins, the lack of cutting edges on the dentition, the teeth orientated forward in the mouth and a tubular low-strength rostrum is in marked contrast to the contemporaneous subclade Geosaurini which had: high-strength brevirostrine-mesorostrine rostra, carinated and serrated dentition, vertically orientated tooth crowns positioned to maximize shear, a low overall tooth count (<15 teeth per maxilla and dentary) and an increased gape [14], [16], [18], [43], [81], [83], [84].…”

Section: Discussionmentioning

confidence: 99%

“…1). Rhacheosaurins are not only characterised by having skulls not suited for enduring strong bite forces, but have elongate and tubular snouts, high tooth counts, and uncarinated and unserrated teeth [14], [16], [18] (although three specimens do have carinae: [19], [20]–[21]). Based on this craniodental morphology it has been posited that they were well suited for feeding on small, fast-moving prey [14], [16].…”

Section: Introductionmentioning

confidence: 99%

“…Interestingly, rhacheosaurins also exhibit a temporal and phylogenetic trend towards increasing marine specialisation (e.g. posterior retraction of the external nares, regression of the calcaneum tuber, increase in caudal vertebrae count in the tail fluke [14], [20]). Currently, all discovered species within Rhacheosaurini are known from the Late Jurassic and Early Cretaceous [1], [16], [20], [22], [23], [24].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

The First Metriorhynchid Crocodylomorph from the Middle Jurassic of Spain, with Implications for Evolution of the Subclade Rhacheosaurini

et al. 2013

View full text Add to dashboard Cite

BackgroundMarine deposits from the Callovian of Europe have yielded numerous species of metriorhynchid crocodylomorphs. While common in English and French Formations, metriorhynchids are poorly known from the Iberian Peninsula. Twenty years ago an incomplete, but beautifully preserved, skull was discovered from the Middle Callovian of Spain. It is currently the oldest and best preserved metriorhynchid specimen from the Iberian Peninsula. Until now it has never been properly described and its taxonomic affinities remained obscure.Methodology/Principal FindingsHere we present a comprehensive description for this specimen and in doing so we refer it to a new genus and species: Maledictosuchus riclaensis. This species is diagnosed by numerous autapomorphies, including: heterodont dentition; tightly interlocking occlusion; lachrymal anterior process excludes the jugal from the preorbital fenestra; orbits longer than supratemporal fenestrae; palatine has two non-midline and one midline anterior processes. Our phylogenetic analysis finds Maledictosuchus riclaensis to be the basal-most known member of Rhacheosaurini (the subclade of increasingly mesopelagic piscivores that includes Cricosaurus and Rhacheosaurus).Conclusions/SignificanceOur description of Maledictosuchus riclaensis shows that the craniodental morphologies that underpinned the success of Rhacheosaurini in the Late Jurassic and Early Cretaceous, as a result of increasing marine specialization to adaptations for feeding on fast small-bodied prey (i.e. divided and retracted external nares; reorientation of the lateral processes of the frontal; elongate, tubular rostrum; procumbent and non-carinated dentition; high overall tooth count; and dorsolaterally inclined paroccipital processes), first appeared during the Middle Jurassic. Rhacheosaurins were curiously rare in the Middle Jurassic, as only one specimen of Maledictosuchus riclaensis is known (with no representatives discovered from the well-sampled Oxford Clay Formation of England). As such, the feeding/marine adaptations of Rhacheosaurini did not confer an immediate selective advantage upon the group, and it took until the Late Jurassic for this subclade to dominate in Western Europe.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The First Metriorhynchid Crocodylomorph from the Middle Jurassic of Spain, with Implications for Evolution of the Subclade Rhacheosaurini

et al. 2013

View full text Add to dashboard Cite

show abstract

“…It was discovered by one of us (A.C.) (Hua et al, 2000) and Dakosaurus sp. (Buffetaut, 1982)), late Valanginian teleosaurid crocodyliform (Steneosaurus sp.…”

Section: Introductionmentioning

confidence: 99%

The first definite record of a Valanginian ichthyosaur and its implications on the evolution of post-Liassic Ichthyosauria

Fischer

Clément²,

Guiomar³

et al. 2011

Cretaceous Research

View full text Add to dashboard Cite

A complete ichthyosaur rostrum, with 124 associated teeth, was recently discovered in LauxMontaux locality, department of Drôme, southeastern France. The associated belemnites and ammonites indicate a late Valanginian age (Neocomites peregrinus Zone, Olcostephanus nicklesi Subzone) for this fossil, which consequently represents the first diagnostic ichthyosaur ever reported from Valanginian strata. This specimen also represents the first occurrence of Aegirosaurus outside the Tithonian (Upper Jurassic) lithographic limestones of Bavaria (southern Germany). Tooth morphology and wear pattern suggest that Aegirosaurus belonged to the "Pierce II/ Generalist" feeding guild, which was hitherto not represented in post-Liassic ichthyosaurs. Most Late Jurassic ichthyosaurs actually crossed the Jurassic-Cretaceous boundary.

show abstract

Cranial and endocranial anatomy of a three‐dimensionally preserved teleosauroid thalattosuchian skull

Wilberg

Beyl

Pierce

et al. 2021

The Anatomical Record

View full text Add to dashboard Cite

Thalattosuchians represent one of the several independent transitions into the marine realm among crocodylomorphs. The extent of their aquatic adaptations ranges from the semiaquatic teleosauroids, superficially resembling extant gharials, to the almost cetacean‐like pelagic metriorhynchids. Understanding the suite of osteological, physiological, and sensory changes that accompanied this major transition has received increased attention, but is somewhat hindered by a dearth of complete three‐dimensionally preserved crania. Here, we describe the cranial and endocranial anatomy of a well‐preserved three‐dimensional specimen of Macrospondylus bollensis from the Toarcian of Yorkshire, UK. The trigeminal fossa contains two similar‐sized openings separated by a thin lamina of prootic, a configuration that appears unique to a subset of teleosauroids. Macrospondylus bollensis resembles other thalattosuchians in having pyramidal semicircular canals with elongate cochlear ducts, enlarged carotid canals leading to an enlarged pituitary fossa, enlarged orbital arteries, enlarged endocranial venous sinuses, reduced pharyngotympanic sinuses, and a relatively straight brain with a hemispherical cerebral expansion. We describe for the first time the olfactory region and paranasal sinuses of a teleosauroid. A relatively large olfactory region suggests greater capacity for airborne olfaction in teleosauroids than in the more aquatically adapted metriorhynchoids. Additionally, slight swellings in the olfactory region suggest the presence of small salt glands of lower secretory capacity than those of metriorhynchoids. The presence of osteological correlates for salt glands in a teleosauroid corroborates previous hypotheses that these glands originated in the common ancestor of Thalattosuchia, facilitating their rapid radiation into the marine realm.

show abstract

Enaliosuchus macrospondylus (Crocodylia, Metriorhynchidae) du Valanginien de Barret-le-Bas (Hautes Alpes, France): Un cas unique de remontée des narines externes parmi les crocodiliens

Cited by 26 publications

References 2 publications

The First Metriorhynchid Crocodylomorph from the Middle Jurassic of Spain, with Implications for Evolution of the Subclade Rhacheosaurini

The First Metriorhynchid Crocodylomorph from the Middle Jurassic of Spain, with Implications for Evolution of the Subclade Rhacheosaurini

The first definite record of a Valanginian ichthyosaur and its implications on the evolution of post-Liassic Ichthyosauria

Cranial and endocranial anatomy of a three‐dimensionally preserved teleosauroid thalattosuchian skull

Contact Info

Product

Resources

About