Morphology and function of the hyoid apparatus of fossil xenarthrans (mammalia)

  title={Morphology and function of the hyoid apparatus of fossil xenarthrans (mammalia)},
  author={Leandro Mart{\'i}n P{\'e}rez and N{\'e}stor Toledo and G. De iuliis and M. Susana Bargo and Sergio Fabi{\'a}n Vizcaino},
  journal={Journal of Morphology},
The analysis of the hyoid apparatus of fossil xenarthrans provides insight on the form of the tongue and its function in food intake and intraoral processing. The hyoid apparatus of xenarthrans is notable for fusion among its elements. The presence of a V‐bone, a complex consisting of fused basihyal and thyrohyal bones, is a consistent and probably synapomorphic feature of xenarthrans. Fusion of other elements is variable in fossil xenarthrans. Most fossil sloths retain independent elements, as… 

The evolution of hyoid apparatus in Xenarthra (Mammalia: Eutheria)

The morphology of the hyoid apparatus in xenarthrans is compared, describing its general morphology and variation in each major clade and scoring these variations as phylogenetic characters, which were submitted to ancestral states reconstructions.

New Jurassic mammaliaform sheds light on early evolution of mammal-like hyoid bones

A Jurassic fossil shows that early premammalian ancestors possessed hyoids similar to those seen in mammals today, and a new Jurassic docodontan mammaliaform found in China that is preserved with the hyoid bones is reported.

Description of the stylohyal bone of a giant sloth (Lestodon armatus)

A right stylohyal found in the late Pleistocene megafaunal bonebed of the Arroyo del Vizcaino site, Uruguay is described as two perfectly matched pieces that were within a few centimeters of each other.

A new record of Lestodon armatus Gervais 1855 (Xenarthra, Mylodontidae) from the Quaternary of southern Brazil and remarks on its postcranial anatomy

A new specimen assigned to L. armatus is reported from a Quaternary deposit in Caçapava do Sul, southern Brazil, composed of cranial fragments, vertebrae, articulated hind limb and pes, as well as other post-cranial elements.

Tracing the Paleobiology of Paedotherium and Tremacyllus (Pachyrukhinae, Notoungulata), the Latest Sciuromorph South American Native Ungulates – Part II: Orbital, Auditory, and Occipito-Cervical Regions

The integrative analysis proposed here and in the accompanying contribution aims to shed light on convergences with extant models, paleobiology, niche partitioning, and external appearance of the latest rodent-like ungulates.

Cranial Anatomy and Paleoneurology of the Extinct Sloth Catonyx tarijensis (Xenarthra, Mylodontidae) From the Late Pleistocene of Oruro, Southwestern Bolivia

The combined information from the external and internal anatomy suggests reduced lingual protrusion in Catonyx tarijensis, or at least a consistently more limited protrusion of the tongue in comparison with other mylodontid sloths such as Glossotherium robustum.

Digital Cranial Endocasts of the Extinct Sloth Glossotherium robustum (Xenarthra, Mylodontidae) from the Late Pleistocene of Argentina: Description and Comparison with the Extant Sloths

This study, which represents the first exhaustive analysis of digital endocasts of a fossil sloth, reveals the importance of the application of new methodologies, such as CT scans, for elucidating the evolutionary history of this peculiar mammalian clade.

The howl of Rancho La Brea: Comparative anatomy of modern and fossil canid hyoid bones

This study compares fossilized hyoid elements from Canis dirus and Canis latrans to samples from modern large congeners, namely: Canis lupus (the gray wolf), Canis rufus ( the red wolf), and modern C. latrans.

Anatomy description of cervical region and hyoid apparatus in living giant anteaters Myrmecophaga tridactyla Linnaeus, 1758

The bone contours in the hyoid apparatus of the giant anteater is described by means of radiographic and tomographic images and the presence of air in the oropharynx enabled the assessment of soft tissue structures in this region, such as the epiglottis and the soft palate.



The teeth of the “toothless”: novelties and key innovations in the evolution of xenarthrans (Mammalia, Xenarthra)

  • S. Vizcaino
  • Environmental Science, Geography
  • 2009
The combination of tooth features that characterize xenarthrans might be seen as the key innovation for the ecologic diversity developed at least since the Oligocene, breaking the mold of the tribosphenic condition that constrained the evolution of the other major clades of mammals.

The Morphology and Function of the Hyoid Region in the Tree Sloths, Bradypus and Choloepus

The proposed model of hyoid function predicts that this arrangement aids an inverted sloth in opening the mouth fully against gravity while permitting the hyoid to move anteriorly during tongue extension independent of the sternomandibularis.

Myology of the Feeding Apparatus of Myrmecophagid Anteaters (Xenarthra: Myrmecophagidae)

  • K. Reiss
  • Biology
    Journal of Mammalian Evolution
  • 2004
The musculoskeletal feeding apparatus of anteaters in the family Myrmecophagidae (Eutheria: Xenarthra) is described, compared among the three extant genera, and interpreted in a phylogenetic framework.

Skull Shape, Masticatory Apparatus, and Diet of Vassallia and Holmesina (Mammalia: Xenarthra: Pampatheriidae): When Anatomy Constrains Destiny

The various skeletal and dental features analyzed suggest that the masticatory apparatus of the pampatheres was more powerful and efficient in transverse chewing than in dasypodids and that they were primarily grazers consuming mainly coarse vegetation.

Morphology, evolution and function of feeding in the giant anteater ( Myrmecophaga tridactyla )

Mandibular rotation in lieu of depression and elevation simplifies jaw movements made by a smaller uniquely modified muscle mass over shorter distances, therefore increasing the speed with which anteaters can ingest food, and complements the extremely rapid tongue protrusion–retraction cycle.

The masticatory apparatus of the armadillo Eutatus (Mammalia, Cingulata) and some allied genera: paleobiology and evolution

The analysis of the masticatory apparatus of the eutatines allows us to state that Eutatus and Proeutatus exhibit the most specialized morphology known for an herbivore with an armadillo-like skull pattern.

A peculiar climbing Megalonychidae from the Pleistocene of Peru and its implication for sloth history

The discovery of D. nordenskioldi underscores the great adaptability of Tardigrada: an arboreally adapted form is now added to the already known terrestrial, subarboreal, and aquatic (marine and freshwater) fossil sloths.

Estudio morfofuncional del aparato hioideo de Glyptodon cf. clavipes Owen (Cingulata: Glyptodontidae)

The discovery of an exceptionally well preserved specimen of Glyptodon c/avipes Owen permits a morphofunctional analysis of the hyoid apparatus, which is characterized by the fusion of the stylo-, epi- and ceratohyoid bones of each side into a vertical rod designated here as the sigmohyoids.

The cranial anatomy of Thalassocnus (Xenarthra, Mammalia), a derived nothrothere from the Neogene of the Pisco Formation (Peru)

Abstract The Pisco Formation (Miocene–Pliocene) of Peru contains a diverse marine vertebrate fauna. Among the more unusual members of the fauna is the semi-aquatic to aquatic nothrothere sloth,

Carved teeth and strange jaws: how glyptodonts masticated

In this paper, the highly peculiar masticatory apparatus of glyptodonts is studied. The general morphology of the skull is analysed using a morphometric procedure, the Resistant Fit Theta Rho