Scelidosaurus harrisonii (Dinosauria: Ornithischia) from the Early Jurassic of Dorset, England: biology and phylogenetic relationships

2020 ◽  
Vol 191 (1) ◽  
pp. 1-86
Author(s):  
David B Norman
Keyword(s):  
Functional Analysis ◽  
Phylogenetic Relationships ◽  
Sensory Systems ◽  
Critical Assessment ◽  
Transverse Displacement ◽  
High Angle ◽  
Anatomical Features ◽  
Lower Jaw ◽  
Locomotor Ability ◽  
Limb Proportions

Abstract A layer of keratinous scutes encased the skull of Scelidosaurus. The neurocranium and the associated principal sensory systems of this dinosaur are described. The cranial musculature is reconstructed and a subsequent functional analysis suggests that jaw motion was orthal, allowing pulping of vegetation and some high-angle shearing between opposing teeth. Wishboning of the lower jaw was enabled by transverse displacement of the quadrates, and the long-axis mandibular torsion that occurred during the chewing cycle was permitted by flexibility at the dentary symphysis. Limb proportions and pectoral and pelvic musculature reconstructions suggest that Scelidosaurus was a facultative quadruped of ‘average’ locomotor ability. It retained some anatomical features indicative of a bipedal-cursorial ancestry. Hindlimb motion was oblique-to-parasagittal to accommodate the girth of the abdomen. Scelidosaurus used a combination of costal and abdominally driven aspiration. The hypothesis that respiration was an ‘evolutionary driver’ of opisthopuby in all dinosaurs is overly simplistic. A critical assessment of datasets used to analyse the systematics of ornithischians (and thyreophoran subclades) has led to a revised dataset that positions Scelidosaurus as a stem ankylosaur, rather than a stem thyreophoran. The value of phylogenetic definitions is reconsidered in the light of the new thyreophoran cladogram.

Cranial anatomy of tadpoles of five species of Scinax (Hylidae, Hylinae)

Zootaxa ◽  
2011 ◽  
Vol 2787 (1) ◽  
pp. 19 ◽  
Author(s):  
LEANDRO ALCALDE ◽  
FLORENCIA VERA CANDIOTI ◽  
FRANCISCO KOLENC ◽  
CLAUDIO BORTEIRO ◽  
DIEGO BALDO
Keyword(s):  
Buccal Cavity ◽  
Morphological Data ◽  
Sister Taxon ◽  
Anatomical Features ◽  
Interspecific Relationships ◽  
Lower Jaw ◽  
Lateral Ridge ◽  
Source Of Information

We studied the oral apparatus, buccal cavity and musculoskeletal features in tadpoles of five species of the genus Scinax (S. acuminatus, S. uruguayus, S. aff. pinima, S. aromothyella, and S. berthae). Observed variation is mainly related to intrageneric grouping. Scinax acuminatus (S. ruber clade, sister taxon of S. rostratus group) has a distinctive combination of a mental gap in the margin of oral papillae, straight labial teeth with few or absent cusps, processus muscularis acute and posteriorly directed, and m. subarcualis rectus I with two slips. Scinax uruguayus and S. aff. pinima (S. uruguayus group) have keratinized sheets ventrolateral to the lower jaw sheath, well-developed infralabial and lateral ridge papillae, robust jaw cartilages, cornua trabeculae with short and widely divergent free portions, processus articularis short and wide, processus muscularis thin and directed anteriorly. Scinax aromothyella and S. berthae (S. catharinae group) have poorly developed, non-colored spurs behind the lower jaw sheath, long and thin processus articularis, wide and rounded processus muscularis, and tripartite cartilago suprarostralis. Anatomical features described are congruent with current phylogenetic arrangements based on molecular, chromosomal, and morphological data, and provide a source of information that can be useful to solve interspecific relationships within Scinax.

A new species of Paretroplus (Teleostei: Cichlidae: Etroplinae) from northeastern Madagascar, with a phylogeny and revised diagnosis for the P. damii clade

Zootaxa ◽  
2011 ◽  
Vol 2768 (1) ◽  
pp. 55 ◽  
Author(s):  
JOHN S. SPARKS ◽  
ROBERT C. SCHELLY
Keyword(s):  
New Species ◽  
Anterior Margin ◽  
Pigmentation Pattern ◽  
Anatomical Features ◽  
The North ◽  
Lower Jaw ◽  
Posterior Field ◽  
Breeding Coloration ◽  
Masoala Peninsula ◽  
A New Species

Paretroplus loisellei, a new species of etropline cichlid from Madagascar, is described from the middle to lower reaches of the Mahanara River, located to the north of the Masoala Peninsula in northeastern Madagascar. The new species is recovered within the “Paretroplus damii clade” on the basis of several apomorphic anatomical features, including the presence of a triangular, black or dark gray, pectoral-axil patch, chest scales that are greatly reduced in size and highly embedded, and flank scales in which the posterior field is thin and unossified. The new species is distinguished from its sister taxon, P. damii, by a more or less horizontal profile extending from the anterior margin of the lower jaw to the ventroposterior margin of the suspensorium (vs. strongly rounded and convex), horizontally oriented oral jaws with fleshy lips (vs. oblique and thin), tricuspid symphyseal teeth in the upper jaw with distinct and sharp lateral cusps, a much darker overall pigmentation pattern, and distinctive bright golden breeding coloration (vs. brick red).

ADAPTATIONS OF GALL WASPS OF THE GENUS DIPLOLEPIS (HYMENOPTERA: CYNIPIDAE) AND THE ROLE OF GALL ANATOMY IN CYNIPID SYSTEMATICS

1993 ◽  
Vol 125 (S165) ◽  
pp. 139-163 ◽  
Author(s):  
J.D. Shorthouse
Keyword(s):  
Host Specificity ◽  
Phylogenetic Relationships ◽  
Distinct Species ◽  
Life Cycles ◽  
Organ Specificity ◽  
Anatomical Features ◽  
Gall Wasps ◽  
Structural Differences

AbstractAdaptations and attributes of gall-inducing cynipid wasps are reviewed to emphasize that differences in life cycles and anatomical features of their galls are just as useful for systematic purposes as are structural differences in the adult insects themselves. The extent to which cynipid wasps have specialized is illustrated by the genus Diplolepis, all species of which are restricted to native and introduced roses and induce structurally distinct galls. Various aspects of Diplolepis biology including life cycles, host specificity, and gall development and anatomy are reviewed. The biologies of two species of Diplolepis that commonly co-exist in the same habitat in central Ontario are then examined in detail. Diplolepis polita (Ashmead) induces a single-chambered gall on the leaves of Rosa acicularis Lindl. whereas Diplolepis spinosa (Ashmead) induces a multi-chambered gall on the stems of Rosa blanda Ait. Differences in life cycles, distribution, host and organ specificity, oviposition, gall initiation and development, along with differences in the communities of parasitoids and inquilines attracted to the galls, confirm the existence of distinct species and allow some speculation on their ecological and phylogenetic relationships.

Nearly complete skeleton of Tetraclaenodon (Mammalia, Phenacodontidae) from the early Paleocene of New Mexico: morpho-functional analysis

2012 ◽  
Vol 86 (1) ◽  
pp. 25-43 ◽  
Author(s):  
Peter E. Kondrashov ◽  
Spencer G. Lucas
Keyword(s):  
Functional Analysis ◽  
Phylogenetic Analysis ◽  
New Mexico ◽  
Phylogenetic Relationships ◽  
Morphological Features ◽  
Postcranial Skeleton ◽  
Terrestrial Mammal ◽  
San Juan Basin ◽  
The Family ◽  
Early Paleocene

We describe the relatively complete skeleton of Tetraclaenodon undoubtedly associated with its dentition, from the Torrejonian interval of the Nacimiento Formation in the San Juan Basin, New Mexico. Tetraclaenodon is the most primitive and oldest genus of the family Phenacodontidae and is very important for assessing the phylogenetic relationships of the family. The newly described skeleton belonged to a lightly built terrestrial mammal that could use trees for shelter. The structure of the ulna, manus, femur, crus, and pes corresponds to that of a typical terrestrial mammal, while morphological features such as the low greater tubercle of the humerus, long deltopectoral crest, pronounced lateral supracondylar crest, and hemispherical capitulum indicate some scansorial adaptations of Tetraclaenodon. The postcranial skeleton of Tetraclaenodon does not exhibit the cursorial adaptations seen in later phenacodontids and early perissodactyls. Phylogenetic analysis did not recover monophyletic “Phenacodontidae”; instead, phenacodontids formed a series of sister taxa to the Altungulata clade. Tetraclaenodon is the basal-most member of the “Phenacodontidae” + Altungulata clade.

scholarly journals Correlation analysis of craniomandibular index and gothic arch tracing in patients with craniomandibular disorders

2011 ◽  
Vol 68 (7) ◽  
pp. 594-601 ◽  
Author(s):  
Jelena Todic ◽  
Dragoslav Lazic ◽  
Radiovoje Radosavljevic
Keyword(s):  
Functional Analysis ◽  
Temporomandibular Joint ◽  
Lateral Asymmetry ◽  
Jaw Movements ◽  
Craniomandibular Dysfunction ◽  
Lateral Dislocation ◽  
Lower Jaw ◽  
Joint Disorder ◽  
Functional Analyses ◽  
Gothic Arch

Background/Aim. Complex etiology and symptomatology of craniomandibular dysfunction make the diagnosing and therapy of this disorder more difficult. The aim of this work was to assess the value of clinical and instrumental functional analyses in diagnosing of this type of disorders. Methods. In this study 200 subjects were examined, 15 with temporomandibular joint disorder. They were subjected to clinical functional analysis (Fricton-Shiffman) and instrumental functional analysis by using the method of gothic arch. The parameters of the gothic arch records were analyzed and subsequently compared among the subjects of the observed groups. Results. In the examined group of the population 7.5% of them were with craniomandibular dysfunction. The most frequent symptoms were sound in temporomandibular joint, painful sensitivity of the muscles on palpation and lateral turning of the lower jaw while opening the mouth. By analyzing the gothic arch records and comparing the obtained values between the observed groups it was assessed that: lateral and protrusion movements, lateral amplitude and the size of gothic arch were much bigger in the healthy subjects, and latero-lateral asymmetry was larger in the sick subjects. Latero-lateral dislocation of apex was recorded only in the sick subjects with average values of 0.22 ? 0.130 mm. The correlation between the values of Fricton-Shiffman craniomandibular index and the parameters of the gothic arch records and latero-lateral amplitude and dislocation of apex records were established by correlative statistical analysis. Conclusion. Functional analysis of orofacial system and instrumental analysis of lower jaw movements (gothic arch method) can be recommended as precise and simple methods in diagnosing craniomandibular dysfunctions.

scholarly journals A new short-necked chelid turtle from the Loncoche Formation (Late Campanian- Early Maastrichtian) Mendoza province, Argentina: Macro, microanatomy, and preliminary phylogenetic relationships

2015 ◽  
Author(s):  
Marcelo de la Fuente ◽  
Ignacio Maniel ◽  
Juan Marcos Jannello ◽  
Juliana Sterli ◽  
Bernardo González Riga ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Cancellous Bone ◽  
Phylogenetic Relationships ◽  
Cervical Vertebrae ◽  
Data Matrix ◽  
Appendicular Skeleton ◽  
Thin Sections ◽  
Lower Jaw ◽  
A New Species ◽  
Preliminary Phylogenetic Analysis

Background. The lower section of the Loncoche Formation (Late Campanian-Early Maastrichtian) outcropping at Ranquil-Có locality (Mendoza province, Argentina) has yielded a rich assemblage of vertebrates that was studied in 1995 by Gonzalez Riga. According to this author these vertebrate remains were found in a tidal paleoenvironment, resulting from transportation, mixing and deposition of continental remains mixed with those from near costal environments. Previously to these findings Jose F. Bonaparte recovered in 1990 a large turtle from the same locality and horizon. Methods. Remains of basicranium (basioccipital and basisphenoid), fragments of both quadrates, left opisthotic, a lower jaw, cervical vertebrae, one caudal vertebra, appendicular skeleton, a partial carapace and one almost complete plastron are preserved in MACN Pv M2. In order to explore the phylogenetic relationships of MACN Pv M2, this specimen was included in a data matrix built up by 48 characters and 17 taxa. One fragmentary costal plate was sampled for histological analysis. The bone microstructure of the thin sections was studied under light microscopy using normal and polarized lights. Results. The preliminary phylogenetic analysis suggests that MACN Pv M2 is nested in a clade also including Phrynops hilarii + Mesoclemmys nasuta + long-necked chelids. The pelvic girdle attached by suture to the shell in MACN Pv M2 and the synapomorphic characters such as splenial bone in the lower jaw, ilium extending over the eight costal and anterior margin of the suprapygal bones allow us to assign this specimen to Pleurodira Chelidae. The microanatomy of MACN Pv M2 shows a diploe structure as in other turtles. The internal cortex is equal or slowly thinner than the external one, and the cancellous bone occupy the main proportion (50-60%). The external cortex is composed of structural fibre bundles that extend parallel to the external surface and orient longitudinally and transversally to the progression of the elements. The cancellous bone is mostly well developed. The internal cortex consists of parallel-fibred bone that locally can grade into lamellar bone. Discussion. The unique combination of plesiomorphies (such as lateral mesoplastra, area articularis mandibularis concave, a short midline epiplastral suture, an anterior peripherals bones shorter than posterior ones) and autapomorphies (such as both rami of the lower jaw fused, extremely wide anterior plastral lobe, and a slightly epiplastral notch) recovered in this phylogenetic analysis allow to assigned MACN Pv M2 as a new species of short-necked chelid taxa. The histology of MACN Pv M2 shows features that suggest adaptation to the aquatic lifestyle (i.e., well vascularized external cortex, the vascularization of the internal cortex composed of scattered vascular canals and primary osteons of longitudinally orientation).

scholarly journals A new short-necked chelid turtle from the Loncoche Formation (Late Campanian- Early Maastrichtian) Mendoza province, Argentina: Macro, microanatomy, and preliminary phylogenetic relationships

2015 ◽  
Author(s):  
Marcelo de la Fuente ◽  
Ignacio Maniel ◽  
Juan Marcos Jannello ◽  
Juliana Sterli ◽  
Bernardo González Riga ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Cancellous Bone ◽  
Phylogenetic Relationships ◽  
Cervical Vertebrae ◽  
Data Matrix ◽  
Appendicular Skeleton ◽  
Thin Sections ◽  
Lower Jaw ◽  
A New Species ◽  
Preliminary Phylogenetic Analysis

Background. The lower section of the Loncoche Formation (Late Campanian-Early Maastrichtian) outcropping at Ranquil-Có locality (Mendoza province, Argentina) has yielded a rich assemblage of vertebrates that was studied in 1995 by Gonzalez Riga. According to this author these vertebrate remains were found in a tidal paleoenvironment, resulting from transportation, mixing and deposition of continental remains mixed with those from near costal environments. Previously to these findings Jose F. Bonaparte recovered in 1990 a large turtle from the same locality and horizon. Methods. Remains of basicranium (basioccipital and basisphenoid), fragments of both quadrates, left opisthotic, a lower jaw, cervical vertebrae, one caudal vertebra, appendicular skeleton, a partial carapace and one almost complete plastron are preserved in MACN Pv M2. In order to explore the phylogenetic relationships of MACN Pv M2, this specimen was included in a data matrix built up by 48 characters and 17 taxa. One fragmentary costal plate was sampled for histological analysis. The bone microstructure of the thin sections was studied under light microscopy using normal and polarized lights. Results. The preliminary phylogenetic analysis suggests that MACN Pv M2 is nested in a clade also including Phrynops hilarii + Mesoclemmys nasuta + long-necked chelids. The pelvic girdle attached by suture to the shell in MACN Pv M2 and the synapomorphic characters such as splenial bone in the lower jaw, ilium extending over the eight costal and anterior margin of the suprapygal bones allow us to assign this specimen to Pleurodira Chelidae. The microanatomy of MACN Pv M2 shows a diploe structure as in other turtles. The internal cortex is equal or slowly thinner than the external one, and the cancellous bone occupy the main proportion (50-60%). The external cortex is composed of structural fibre bundles that extend parallel to the external surface and orient longitudinally and transversally to the progression of the elements. The cancellous bone is mostly well developed. The internal cortex consists of parallel-fibred bone that locally can grade into lamellar bone. Discussion. The unique combination of plesiomorphies (such as lateral mesoplastra, area articularis mandibularis concave, a short midline epiplastral suture, an anterior peripherals bones shorter than posterior ones) and autapomorphies (such as both rami of the lower jaw fused, extremely wide anterior plastral lobe, and a slightly epiplastral notch) recovered in this phylogenetic analysis allow to assigned MACN Pv M2 as a new species of short-necked chelid taxa. The histology of MACN Pv M2 shows features that suggest adaptation to the aquatic lifestyle (i.e., well vascularized external cortex, the vascularization of the internal cortex composed of scattered vascular canals and primary osteons of longitudinally orientation).

scholarly journals The Influence of Exams Stress on Brux Activity in Russian Dental Students

2018 ◽  
Vol 11 (4) ◽  
pp. 2051-2059
Author(s):  
D. V. Medovnikova ◽  
A. S. Ytuzh ◽  
M. G. Soykher ◽  
I. K. Pisarenko ◽  
A. S. Onyanova
Keyword(s):  
Functional Analysis ◽  
Dental Students ◽  
The Other ◽  
Research Protocol ◽  
Single Group ◽  
Group Design ◽  
Lower Jaw ◽  
Negative Effect ◽  
Exam Stress ◽  
Upper Jaw

The study assessed stress and brux activity among dental students during exam (stress) and non-examination (non-stress) periods. The study was initiated as a single group design with the total number of participants 36 (25 females and 11 males). All the participants were examined twice (once in a stress period and once in a non-stress period) according to “Clinical Functional Analysis”, which includes questions about students’ medical and dental history, as well as muscle palpation results. Two «BruxCheckers» (BCs) were applied, one for the upper jaw, the other for the lower jaw, two times for examination and non-examination periods. After the use, the «BCs» were photographed according to the research protocol and the abraded facets area on «BCs» was calculated in square millimeters. The research showed that during a stress period students may have headaches, cramps and pain in shoulder and neck muscles. The research also revealed that during the stress situation the abraded area shifts from frontal teeth to chewing teeth and brux episodes can occur more frequently and with a higher load. Chewing teeth (premolars in our study) are more adapted and more useful for such a condition. Accordingly, our students shifted their brux behavior from teeth 33 and 31 to teeth 15 and 24. Therefore, exams are a strong stress factor for dental students. In turn, prolongated stress can be an indicator of risk factor and have a negative effect for health of the craniomandibular system.

Anatomy and functional morphology of the largest marine reptile known, Mosasaurus hoffmanni (Mosasauridae, Reptilia) from the Upper Cretaceous, Upper Maastrichtian of The Netherlands

1995 ◽  
Vol 347 (1320) ◽  
pp. 155-180 ◽  
Keyword(s):  
Functional Analysis ◽  
The Netherlands ◽  
Functional Morphology ◽  
Upper Cretaceous ◽  
Lower Jaw ◽  
Olfactory Organs ◽  
Marine Reptile ◽  
Four Bar Linkage ◽  
First Time ◽  
Upper Maastrichtian

Mosasaurus hoffmanni , one of the latest known mosasaurs, comes from the Upper Maastrichtian, Upper Cretaceous Chalk of The Netherlands. Although the first specimen was discovered over 200 years ago, it is here fully described for the first time to provide detailed insights into its anatomy, functional morphology and evolution. Many characters of the skull show that M. hoffmanni was among the most advanced mosasaurs. The skull is robustly constructed and is the least kinetic in the Mosasauridae and, with a tightly assembled palatal complex, provided greater cranial stability in this large-headed mosasaur. The cranial musculature is highly modified. The four-bar linkage system of lizards and early mosasaurs is non-functional in M. hoffmanni . The elements of the lower jaw are also more tightly united than in other mosasaurs. Tooth crowns are divided into several distinct, unique cutting surfaces or prisms. A functional analysis of the marginal teeth shows that they are particularly adapted to powerful bite forces although pterygoidal teeth are small and reduced in importance in ratchet feeding. Moderately large orbits and poorly developed olfactory organs suggest that Mosasaurus hoffmanni was a surface-swimming animal. A relatively lower level of binocular vision than in some other mosasaurs may indicate a somewhat uncomplicated habitat. Geological and palaeontological evidence indicates that M. hoffmanni lived in fairly deep nearshore waters of 40—50 m depth, with changing temperatures and rich vertebrate and invertebrate life. Several severely broken and healed mandibles suggest either a violent lifestyle in predation or in fighting.

Some morphological and anatomical features of the Monotypic genus Bryobartramia Sainsbury (Musci)

1977 ◽  
Vol 25 (2) ◽  
pp. 141 ◽  
Author(s):  
IG Stone
Keyword(s):  
Phylogenetic Relationships ◽  
Monotypic Genus ◽  
Anatomical Features

Some previously unreported features of the moss Bryobartramia including details of the development of its remarkable inflated epigonium are described. A comparison is made with two other genera, Trachycarpidium and Encalypta, with some discussion on the possible phylogenetic relationships of Bryobartramia.

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