New Quaternary teiid (Lepidosauria, Squamata) lizard remains from Gruta do Urso, Tocantins, Brazil

Hsiou, Annie Schmaltz; Schubert, Blaine W.; Winck, Gisele R.; Onary, Silvio; Avilla, Leonardo dos Santos

doi:10.4072/rbp.2016.2.07

Cited by 6 publications

(7 citation statements)

References 35 publications

(49 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The specimen material comprised two adult female specimens (T1 and T3) of the South American tegu lizard, S. merianae (= Tupinambis merianae ) [ 53 ]. This taxon and closely related species (such as Dracaena guianensis ) are relatively well known in terms of their specific differences and phylogenetic relationships [ 53 , 54 ], dentition [ 55 , 56 ], diet [ 57 ], skull shape [ 56 , 58 ], fossil record [ 59 , 60 ], prey transport behaviour [ 61 , 62 ], physiology [ 63 ] and jaw muscles [ 52 , 64 ]. Tegus are known to eat plant material as well as taking a wide variety of prey items including both vertebrates and invertebrates (e.g.…”

Section: Methodsmentioning

confidence: 99%

The biomechanical role of the chondrocranium and sutures in a lizard cranium

Jones

Gröning

Dutel

et al. 2017

J. R. Soc. Interface.

View full text Add to dashboard Cite

The role of soft tissues in skull biomechanics remains poorly understood. Not least, the chondrocranium, the portion of the braincase which persists as cartilage with varying degrees of mineralization. It also remains commonplace to overlook the biomechanical role of sutures despite evidence that they alter strain distribution. Here, we examine the role of both the sutures and the chondrocranium in the South American tegu lizard Salvator merianae. We use multi-body dynamics analysis (MDA) to provide realistic loading conditions for anterior and posterior unilateral biting and a detailed finite element model to examine strain magnitude and distribution. We find that strains within the chondrocranium are greatest during anterior biting and are primarily tensile; also that strain within the cranium is not greatly reduced by the presence of the chondrocranium unless it is given the same material properties as bone. This result contradicts previous suggestions that the anterior portion (the nasal septum) acts as a supporting structure. Inclusion of sutures to the cranium model not only increases overall strain magnitudes but also leads to a more complex distribution of tension and compression rather than that of a beam under sagittal bending.

show abstract

Section: Methodsmentioning

confidence: 99%

The biomechanical role of the chondrocranium and sutures in a lizard cranium

Jones

Gröning

Dutel

et al. 2017

J. R. Soc. Interface.

View full text Add to dashboard Cite

show abstract

“…AMU-CURS-721 differs from extinct †Paradracaena colombiana (Estes 1961) (originally described from the middle Miocene of Colombia, Estes 1961, but also present in the Miocene of Brazil, Peru, Pujos et al 2009) in the nearly straight orientation of the dorsal edge of the dentary. Conversely, the morphology of AMU-CURS-721 is broadly congruent with that of Salvator and Tupinambis, whose comparative osteological diagnosis is still unknown (Hsiou et al 2016) despite it having a relevant interest for paleontologists due to the rich fossil record of Tupinambis-like taxa (see Albino et al 2006;Albino and Brizuela 2014). Waiting for a full description of the dentary of these two recently separated taxa (Harvey et al 2012), AMU-CURS-721 is here referred to Tupinambis s.l.…”

Section: Materialmentioning

confidence: 99%

A Pliocene–Pleistocene continental biota from Venezuela

Carrillo-Briceño

Sánchez²,

Scheyer

et al. 2021

Swiss J Palaeontol

View full text Add to dashboard Cite

The Pliocene–Pleistocene transition in the Neotropics is poorly understood despite the major climatic changes that occurred at the onset of the Quaternary. The San Gregorio Formation, the younger unit of the Urumaco Sequence, preserves a fauna that documents this critical transition. We report stingrays, freshwater bony fishes, amphibians, crocodiles, lizards, snakes, aquatic and terrestrial turtles, and mammals. A total of 49 taxa are reported from the Vergel Member (late Pliocene) and nine taxa from the Cocuiza Member (Early Pleistocene), with 28 and 18 taxa reported for the first time in the Urumaco sequence and Venezuela, respectively. Our findings include the first fossil record of the freshwater fishes Megaleporinus, Schizodon, Amblydoras, Scorpiodoras, and the pipesnake Anilius scytale, all from Pliocene strata. The late Pliocene and Early Pleistocene ages proposed here for the Vergel and Cocuiza members, respectively, are supported by their stratigraphic position, palynology, nannoplankton, and 86Sr/88Sr dating. Mammals from the Vergel Member are associated with the first major pulse of the Great American Biotic Interchange. In contrast to the dry conditions prevailing today, the San Gregorio Formation documents mixed open grassland/forest areas surrounding permanent freshwater systems, following the isolation of the northern South American basin from western Amazonia. These findings support the hypothesis that range contraction of many taxa to their current distribution in northern South America occurred rapidly during at least the last 1.5 million years.

show abstract

“…24 According to Sullivan and Estes 9 and Nydam and Cifelli 25 , Paradracaena also possessed pseudo-thecodont dentition and dentary with an accentuated curvature. Such characteristics are shared with D. guianensis which possess dentary implants and sub-pleurodont condition 8,16 (Figs 2B, 3B).…”

Section: Gastrointestinal Tractmentioning

confidence: 89%

“…For the comparisons with other teiid species, anatomical descriptions from A. ameiva, Salvator merianae, and the extinct Paradracaena sp., were accessed from the literature. 10,15,16 The anatomical descriptions were based on the following references: Estes and Williams 17 and Hsou et al 16 for teeth nomenclature, Romer 3 for osteology, and Herrel et al 18 for myology. This study had the allowance of the Comitê de Ética no Uso de Animais (CEUA) from the Federal University of Acre through CEUA-86/2015, and also had the approval from SISBIO n. 48632-1.…”

Section: Methodsmentioning

confidence: 99%

Revisiting the feeding anatomy of the semi-aquatic lizard Dracaena guianensis Daudin, 1801 (Reptilia, Sauria) from the Western Brazilian Amazon

Leite¹,

Poscai²,

Casas³

2021

JMS

View full text Add to dashboard Cite

Introduction: There are about 842 reptile species known in Brazil, including 799 Squamata, being the most diverse assemblage, comprising 72 amphisbaenians, 276 lizards, and 405 snakes. Lizards have adapted to different habitats with terrestrial, fossorial, arboreal, and semi-aquatic habits. These ecological differences are reflected in skull morphology, with structures that evolved following their dietary specificity. Teiid lizard Dracaena guianensis Daudin, 1801 inhabits swamps and spends most of its time on low trees, though feeding only occurs in water. Its feeding habits are different from other family members, and its diet is mostly composed of mollusks and crustaceans. Herein, the anatomy of feeding apparatus of D. guianensis population from the Western Brazilian Amazon was dissected and documented in four exemplars for the first time. As result, it presents a dorsoventrally compressed neurocranium, dorsally oriented orbits, and heterodont dentition. Those characteristics were different from the most family members, as observed in comparisons with Ameiva ameiva (Linnaeus, 1758), which presents lateral orbits, a cranium not compressed dorsoventrally, and homodont dentition. Furthermore, in D. guianensis, it was possible to verify that muscles related to food apprehension were extremely developed, such as adductors and hyolingual muscles, which increase bite force according to the force versus cutting area in cross section; while in A. ameiva the muscles presented smaller cross sectional area and consequently, less bite force. The correlation between the anatomy of feeding apparatus and stomach contents allowed a preliminary comparison of osteological and myological characteristics to its food habits, suggesting that heterodont condition was a selective pressure directly related to durophagy.

show abstract

New Quaternary teiid (Lepidosauria, Squamata) lizard remains from Gruta do Urso, Tocantins, Brazil

Cited by 6 publications

References 35 publications

The biomechanical role of the chondrocranium and sutures in a lizard cranium

The biomechanical role of the chondrocranium and sutures in a lizard cranium

A Pliocene–Pleistocene continental biota from Venezuela

Revisiting the feeding anatomy of the semi-aquatic lizard Dracaena guianensis Daudin, 1801 (Reptilia, Sauria) from the Western Brazilian Amazon

Contact Info

Product

Resources

About