Swimming capabilities of Mesozoic marine reptiles: implications for method of predation

Paleobiology ◽  
1988 ◽  
Vol 14 (2) ◽  
pp. 187-205 ◽  
Author(s):  
Judy A. Massare
Keyword(s):  
Swimming Speed ◽  
Teleost Fish ◽  
Body Shape ◽  
Total Drag ◽  
Marine Reptiles ◽  
Major Factors ◽  
Marine Reptile

Body shape and mode of swimming were major factors that affected the swimming capabilities of Mesozoic marine reptiles. By estimating the total drag and the amount of energy available through metabolism, the maximum sustained swimming speed was calculated for 115 marine reptile specimens. Calculated sustained swimming speeds range from 1.8 to 2.7 m/sec, but are probably too high by as much as a factor of two. Mesozoic marine reptiles were probably much slower than modern toothed whales. The diversification of fast, agile teleost fish in the Cretaceous may have therefore contributed to the decline of the marine reptiles.Long-bodied reptiles appear to have had slower sustained swimming speeds than deep-bodied forms of the same length. For a given length, ichthyosaurs were probably faster sustained swimmers than plesiosaurs, and plesiosaurs were probably faster sustained swimmers than crocodiles and mosasaurs. This suggests that the long-bodied forms probably used an ambush technique to capture prey, to maximize the range of possible prey and to minimize competition with the faster pursuit predators.

Swimming speed estimation of extinct marine reptiles: energetic approach revisited

Paleobiology ◽  
2002 ◽  
Vol 28 (2) ◽  
pp. 251-262 ◽  
Author(s):  
Ryosuke Motani
Keyword(s):  
Mathematical Model ◽  
Metabolic Rate ◽  
Swimming Speed ◽  
Body Shape ◽  
Speed Estimation ◽  
The Past ◽  
Marine Reptiles ◽  
Energetic Approach ◽  
Shape Models ◽  
Significant Tendency

Cruising speeds of Mesozoic marine reptiles have been estimated in the past by using a mathematical model of energetic equilibrium during steady swimming. This method suffered from a significant tendency to overestimate speeds of extant cetaceans for no clear reason, which raised questions about the validity of the approach itself. The present study identifies the factors that caused this shortcoming and proposes corrections and some additional modifications. These include the use of more accurate body shape models, updated metabolic rate models, and optimal rather than critical swimming speeds. The amended method successfully approximates published optimal speeds of several extant marine vertebrates, including cetaceans, showing that the basic framework of the energetic approach is valid. With this confirmation, the method was applied to Mesozoic marine reptiles, by assuming three different metabolic rate categories known in extant swimming vertebrates (i.e., average ectothermic, raised ectothermic, and marine endothermic levels). The results support previous inferences about the relative cruising capabilities of Mesozoic marine reptiles (i.e., ichthyosaurs > plesiosaurs > mosasaurs). Stenopterygius, a thunniform ichthyosaur, was probably capable of cruising at a speed at least comparable to those reported for some extant thunniform teleosts with similar diets (~1 m/second).

A review of Pachyvaranus crassispondylus Arambourg, 1952, a pachyostotic marine squamate from the latest Cretaceous phosphates of Morocco and Syria

2010 ◽  
Vol 148 (2) ◽  
pp. 237-249 ◽  
Author(s):  
ALEXANDRA HOUSSAYE ◽  
NATHALIE BARDET ◽  
JEAN-CLAUDE RAGE ◽  
XABIER PEREDA SUBERBIOLA ◽  
BAÂDI BOUYA ◽  
...  
Keyword(s):  
Marine Environment ◽  
Teleost Fish ◽  
Shallow Marine ◽  
Shallow Marine Environment ◽  
Southern Margin ◽  
Mode Of Life ◽  
Aquatic Mode ◽  
The Mediterranean ◽  
Marine Reptile ◽  
Detailed Diagnosis

AbstractThe discovery of new specimens of Pachyvaranus crassispondylus Arambourg, 1952 from the Maastrichtian phosphates of Morocco and Syria enables us to (1) redescribe in detail this poorly known varanoid lizard, (2) provide a more detailed diagnosis and (3) re-evaluate the systematic affinities of this taxon within squamates. The latter is placed in Pachyvaranidae nov., considered a new unranked clade of non-pythonomorph Varanoidea. The intense pachyosteosclerosis observed in the vertebrae and ribs suggests a primarily aquatic mode of life for Pachyvaranus. This is in accordance with the sedimentological context (shallow marine environment). As for its palaeobiogeographical distribution, Pachyvaranus is a component of the marine reptile assemblages from the southern margin of the Mediterranean Tethys, around palaeolatitudes 20° N. The osteoderms previously referred to this taxon by Arambourg are reanalysed and assigned to a teleost fish.

The Middle Triassic marine reptile biodiversity in the Germanic Basin, in the centre of the Pangaean world

2012 ◽  
Vol 4 (1) ◽  
Author(s):  
Cajus Diedrich
Keyword(s):  
Middle Triassic ◽  
Coastal Areas ◽  
Skeletal Remains ◽  
Southern Germany ◽  
Shallow Marine ◽  
Germanic Basin ◽  
Marine Reptiles ◽  
Marine Habitats ◽  
Reptile Species ◽  
Marine Reptile

AbstractThe Middle Triassic fossil reptile localities near Bayreuth (Bavaria, southern Germany) consist of shallow marine autochthonous glauconitic marls and terebratulid-rich tempestite carbonates of the newly defined Bindlach and Hegnabrunn formations. Single bones and incomplete skeletons of marine reptiles have been recorded in bone beds within in the Illyrian and Fassanian stages. These include the remains of the sauropterygians Neusticosaurus sp., Lariosaurus cf. buzzii [1], Nothosaurus mirabilis [2], Paranothosaurus giganteus [2], Placodus gigas [3], Cyamodus rostratus [4], Cyamodus münsteri [5], Pistosaurus longaevus [6], and ichthyosaursOmphalosaurus sp., and Shastasaurus sp. or proterosaur Tanystrophaeus conspicuus [7]. New skeletal reconstructions are based on the osteological analysis of three dimensionally preserved bones and skeletal remains. The large number of marine endemic placodont macroalgae feeders (P. gigas) in the Bayreuth sites coincides with the presence of invertebrate palaeocommunities that are characteristic of macroalgae meadow paleoenvironments. Most of the reptile species and genera from the Bayreuth localities also occur in beds of similar ages from the Monte San Giorgio (Switzerland/Italy) or Perledo (Italy) lagoonal areas. Ichthyosaurs and pistosaurs were adapted for open marine conditions, and may have migrated from the Panthalassa Oceans into the shallow marine Germanic Basin to reproduce, whereas placodonts and many other sauropterygians seem to have lived permanently in those shallow marine habitats, with large squamates and thecodont or smaller archosaurs in coastal areas.

Maastrichtian marine reptiles of the Mediterranean Tethys: a palaeobiogeographical approach

2012 ◽  
Vol 183 (6) ◽  
pp. 573-596 ◽  
Author(s):  
Nathalie Bardet
Keyword(s):  
New Jersey ◽  
Northern Margin ◽  
Marine Reptiles ◽  
Global Comparison ◽  
The Mediterranean ◽  
And Cluster Analysis ◽  
Marine Reptile ◽  
Warm Temperate ◽  
Relative Scarcity ◽  
Southern Tethys

AbstractA global comparison of coeval Maastrichtian marine reptiles (squamates, plesiosaurs, chelonians and crocodyliformes) of Europe, New Jersey, northwestern Africa and Middle-East has been performed. More than twenty outcrops and fifty species (half of them being mosasaurids) have been recorded. PEA and Cluster Analysis have been performed using part of this database and have revealed that marine reptile faunas (especially the mosasaurid ones) from the Mediterranean Tethys are clearly segregated into two different palaeobiogeographical provinces: 1) The northern Tethys margin province (New Jersey and Europe), located around palaeolatitudes 30-40°N and developping into warm-temperate environments, is dominated by mosasaurid squamates and chelonioid chelonians; it is characterized by the mosasaurid association of Mosasaurus hoffmanni and Prognathodon sectorius. 2) The southern Tethys margin province (Brazil and the Arabo-African domain), located between palaeolatitudes 20°N-20°S and developping into intertropical environments, is dominated by mosasaurid squamates and bothremydid chelonians; it is characterized by the mosasaurid association of Globidens phosphaticus as well as by Halisaurus arambourgi and Platecarpus (?) ptychodon (Arabo-African domain). These faunal differences are interpreted as revealing palaeoecological preferences probably linked to differences in palaeolatitudinal gradients and/or to palaeocurrents.On a palaeoecological point on view and concerning mosasaurids, the mosasaurines (Prognathodon, Mosasaurus, Globidens and Carinodens) prevail on both margins but with different species. The ichthyophageous plioplatecarpines Plioplatecarpus (Northern margin) and Platecarpus (?) ptychodon (Southern margin) characterise respectively each margin. The halisaurine Halisaurus is present on both margins but with different species. Of importance, the tylosaurines remain currently unknown on the southern Tethys margin and are restricted to higher palaeolatitudes. Chelonians (bothremydids and chelonioids) are respective of each margin, which probably indicates lower dispersal capabilities compared to mosasaurids. The relative scarcity of plesiosaurs and crocodyliformes could be linked to different ecological preferences. The noteworthy crocodyliforme diversity increase in the Palaeogene is probably linked to mosasaurid extinction during the biological crisis of the K/Pg boundary.

scholarly journals An injured pachypleurosaur (Diapsida: Sauropterygia) from the Middle Triassic Luoping Biota indicating predation pressure in the Mesozoic

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Qiling Liu ◽  
Tinglu Yang ◽  
Long Cheng ◽  
Michael J. Benton ◽  
Benjamin C. Moon ◽  
...  
Keyword(s):  
Middle Triassic ◽  
Large Body ◽  
Morphological Characters ◽  
Predation Pressure ◽  
The Body ◽  
West China ◽  
Marine Reptiles ◽  
Large Predator ◽  
The Right ◽  
Marine Reptile

AbstractThe Middle Triassic Luoping Biota in south-west China represents the inception of modern marine ecosystems, with abundant and diverse arthropods, fishes and marine reptiles, indicating recovery from the Permian–Triassic mass extinction. Here we report a new specimen of the predatory marine reptile Diandongosaurus, based on a nearly complete skeleton. The specimen is larger than most other known pachypleurosaurs, and the body shape, caniniform teeth, clavicle with anterior process, and flat distal end of the anterior caudal ribs show its affinities with Diandongosaurus acutidentatus, while the new specimen is approximately three times larger than the holotype. The morphological characters indicate that the new specimen is an adult of D. acutidentatus, allowing for ontogenetic variation. The fang-like teeth and large body size confirm it was a predator, but the amputated hind limb on the right side indicate itself had been predated by an unknown hunter. Predation on such a large predator reveals that predation pressure in the early Mesozoic was intensive, a possible early hint of the Mesozoic Marine Revolution.

Short Note: Second Jurassic marine reptile from the Antarctic Peninsula

2008 ◽  
Vol 21 (2) ◽  
pp. 169-170 ◽  
Author(s):  
Daniel C.H. Hikuroa
Keyword(s):  
Antarctic Peninsula ◽  
Short Note ◽  
Marine Reptiles ◽  
Neuquen Basin ◽  
The Rich ◽  
Neuquén Basin ◽  
Marine Reptile ◽  
The Antarctic

Except for the rich record from the Neuquen Basin (e.g. Gasparini & Fernández 2006), Jurassic southern Gondwanan marine reptiles are relatively rare. A tooth discovered in the Bean Peaks, Ellsworth Land, Antarctic Peninsula (Fig. 1) represents the southernmost, and only the second record of Jurassic marine reptiles from the Antarctic Peninsula. Comprising a single, incomplete tooth, the specimen is unable to be assigned to a species, but the paucity of Gondwanan Jurassic marine reptile material means this find adds significant palaeobiogeographical information.

scholarly journals New highly pachyostotic nothosauroid interpreted as a filter-feeding Triassic marine reptile

2018 ◽  
Vol 14 (8) ◽  
pp. 20180130 ◽  
Author(s):  
Carlos de Miguel Chaves ◽  
Francisco Ortega ◽  
Adán Pérez-García
Keyword(s):  
Upper Triassic ◽  
New Taxon ◽  
Central Spain ◽  
Filter Feeding ◽  
Marine Reptiles ◽  
Marine Reptile

Two well-preserved specimens of a new eosauropterygian from the Upper Triassic of Central Spain are attributed to a new taxon, Paludidraco multidentatus gen. et sp. nov. It is a member of Simosauridae that presents several exclusive characters suggesting a highly specialized trophic adaptation. This discovery increases the already high ecological disparity of the Triassic marine reptiles.

Late Cretaceous (Campanian—Maastrichtian) marine reptiles from the Adaffa Formation, NW Saudi Arabia

2008 ◽  
Vol 145 (5) ◽  
pp. 648-654 ◽  
Author(s):  
B. P. KEAR ◽  
T. H. RICH ◽  
M. A. ALI ◽  
Y. A. AL-MUFARRIH ◽  
A. H. MATIRI ◽  
...  
Keyword(s):  
Saudi Arabia ◽  
North Africa ◽  
Upper Cretaceous ◽  
Arabian Peninsula ◽  
Detailed Report ◽  
Late Mesozoic ◽  
Marine Reptiles ◽  
Lower Maastrichtian ◽  
Marine Reptile ◽  
Lower Campanian

AbstractMarine reptile remains occur in the Upper Cretaceous (lower Campanian to lower Maastrichtian) Adaffa Formation of NW Saudi Arabia. This is the first detailed report of late Mesozoic marine reptiles from the Arabian Peninsula. The fossils include bothremydid (cf. Taphrosphyini) turtles, dyrosaurid crocodyliforms, elasmosaurid plesiosaurs, mosasaurs (Prognathodon, plioplatecarpines) and an indeterminate small varanoid. The assemblage is compositionally similar to contemporary faunas from elsewhere in the Middle East/North Africa, and comprises taxa that are typical of the southern margin of the Mediterranean Tethys.

scholarly journals Ecological pressures and the contrasting scaling of metabolism and body shape in coexisting taxa: cephalopods versus teleost fish

2019 ◽  
Vol 374 (1778) ◽  
pp. 20180543 ◽  
Author(s):  
Hanrong Tan ◽  
Andrew G. Hirst ◽  
Douglas S. Glazier ◽  
David Atkinson
Keyword(s):  
Surface Area ◽  
Teleost Fish ◽  
Body Shape ◽  
Global Climate ◽  
Supply And Demand ◽  
Metabolic Rates ◽  
Metabolic Scaling ◽  
Cephalopod Species ◽  
Physiological Diversity ◽  
Respiratory Gases

Metabolic rates are fundamental to many biological processes, and commonly scale with body size with an exponent ( b R ) between 2/3 and 1 for reasons still debated. According to the ‘metabolic-level boundaries hypothesis', b R depends on the metabolic level ( L R ). We test this prediction and show that across cephalopod species intraspecific b R correlates positively with not only L R but also the scaling of body surface area with body mass. Cephalopod species with high L R maintain near constant mass-specific metabolic rates, growth and probably inner-mantle surface area for exchange of respiratory gases or wastes throughout their lives. By contrast, teleost fish show a negative correlation between b R and L R . We hypothesize that this striking taxonomic difference arises because both resource supply and demand scale differently in fish and cephalopods, as a result of contrasting mortality and energetic pressures, likely related to different locomotion costs and predation pressure. Cephalopods with high L R exhibit relatively steep scaling of growth, locomotion, and resource-exchange surface area, made possible by body-shape shifting. We suggest that differences in lifestyle, growth and body shape with changing water depth may be useful for predicting contrasting metabolic scaling for coexisting animals of similar sizes. This article is part of the theme issue ‘Physiological diversity, biodiversity patterns and global climate change: testing key hypotheses involving temperature and oxygen’.

Sign in / Sign up

Export Citation Format

Share Document