Osteology of Concavispina biseridens (Reptilia, Thalattosauria) from the Xiaowa Formation (Carnian), Guanling, Guizhou, China

2013 ◽  
Vol 87 (2) ◽  
pp. 341-350 ◽  
Author(s):  
Jun Liu ◽  
Li-Jun Zhao ◽  
Chun Li ◽  
Tao He
Keyword(s):  
Phylogenetic Analysis ◽  
Vertebral Column ◽  
Anterior Part ◽  
Cervical Vertebrae ◽  
Eastern Pacific ◽  
Swimming Ability ◽  
Close Relationship ◽  
Basal Position

A thalattosaur taxon, Concavispina biseridens, was recently named and briefly described. It is described here in detail and compared with other thalattosaurs, especially Xinpusaurus. Concavispina is characterized by a long skull, measuring approximately half the length of presacral portion of the vertebral column, two rows of blunt teeth on the anterior part of the maxilla, and neural spines that have convex anterior or posterior margins and V-shaped notches in their dorsal margins. Concavispina differs from all thalattosaurs except Xinpusaurus in that the anterior end of the maxilla is curved dorsally, less than five cervical vertebrae are present, and the proximal end of the humerus is wider than the distal end. Phylogenetic analysis of 40 characters suggests that Miodentosaurus occupies a basal position within Askeptosauridea, Paralonectes is the basalmost member of Thalattosauridea, Concavispina may form a clade with Xinpusaurus, and Chinese thalattosaurs do not have a close relationship with eastern Pacific forms as suggested by previous studies. Concavispina may have been similar to Xinpusaurus in overall locomotor style, but probably had a poorer swimming ability. Concavispina likely differed from Xinpusaurus in diet, for example by depending on softer food.

scholarly journals New information on the Wukongopteridae (Pterosauria) revealed by a new specimen from the Jurassic of China

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2177 ◽  
Author(s):  
Xin Cheng ◽  
Shunxing Jiang ◽  
Xiaolin Wang ◽  
Alexander W.A. Kellner
Keyword(s):  
Phylogenetic Analysis ◽  
Cervical Vertebrae ◽  
Extensor Tendon ◽  
Ontogenetic Stage ◽  
Postcranial Skeleton ◽  
Middle Portion ◽  
Long Tail ◽  
New Information ◽  
Atlas And Axis ◽  
Basal Position

The Wukongopteridae is an important pterosaur group discovered from Yanliao Biota, because it combines character states seen in non-pterodactyloid and pterodactyloid pterosaurs. So far, the Wukongopteridae contains three genera:Wukongopterus,DarwinopterusandKunpengopterus; representing five species. Here we report on a new specimen, IVPP V 17959, that can be undoubtedly referred to the Wukongopteridae based on the presence of a confluent nasoantorbital fenestra, elongated cervical vertebrae (convergent with Pterodactyloidea) and a long tail enclosed by rod-like bony extensions of the zygapophyses. Traits distinguishing this new specimen from other wukongopterid pterosaurs include a premaxilla with a low ossified anterodorsal crest, a nasal bearing the most elongated process known in the Wukongopteridae, and a lacrimal that has a foramen in its middle portion. The new kind of premaxillary crest preserved in IVPP V 17959 suggests that the presence or absence of a premaxillary crest might be an interspecific feature within the Wukongopteridae. A phylogenetic analysis including all wukongopterid pterosaurs recovers IVPP V 17959 in a polytomy withWukongopterusand the species ofDarwinopterus, havingKunpengopterusin a more basal position. The postcranial skeleton of IVPP V 17959 has ontogenetically mature characteristics including a completely fused scapula and coracoid, fused proximal and distal carpal series, and an ossified extensor tendon process of the first wing phalanx, allowing its classification as ontogenetic stage five. Furthermore, the atlas and axis are separated in IVPP V 17959, which indicates that these two bones probably are not fused in skeletally mature wukongopterid individuals.

scholarly journals Russellosaurus coheni n. gen., n. sp., a 92 million-year-old mosasaur from Texas (USA), and the definition of the parafamily Russellosaurina

2005 ◽  
Vol 84 (3) ◽  
pp. 321-333 ◽  
Author(s):  
M.J. Polcyn ◽  
G.L. Bell
Keyword(s):  
Phylogenetic Analysis ◽  
North America ◽  
Common Ancestor ◽  
Dallas County ◽  
Close Relationship ◽  
Definition Of ◽  
Basal Position ◽  
Marine Adaptations

AbstractA new mosasaur, Russellosaurus coheni, is described from the Collignoniceras woollgari Zone (lower Middle Turonian) at Cedar Hill, Dallas County, Texas. At approximately 92 Ma, it is the oldest well-preserved mosasaur skull from North America. It possesses characters diagnostic of Plioplatecarpinae but retains numerous plesiomorphies as well. Phylogenetic analysis indicates a close relationship with Yaguarasaurus columbianus, and these two, together with Tethysaurus nopcsai, form a clade that occupies a position basal to the divergence of the subfamilies Tylosaurinae and Plioplatecarpinae. Russellosaurus coheni is proposed as the nominal taxon of a new mosasaur clade, parafamily taxon novum Russellosaurina, which includes Plioplatecarpinae, Tylosaurinae, their common ancestor and all descendants. Tethysaurus retains a plesiopedal limb and girdle morphology, and along with Russellosaurus and Yaguarasaurus, cranial plesiomorphies. Dallasaurus turneri, a temporally and geographically sympatric plesiopedal mosasaur, occupies a basal position within Mosasaurinae. This phyletic arrangement confirms that marine adaptations, such as development of paddle-like limbs, occurred independently in at least two lineages of mosasaurs, once within Mosasaurinae and once within Russellosaurina.

scholarly journals High Prevalence of Three Potyviruses Infecting Cucurbits in Oklahoma and Phylogenetic Analysis of Cucurbit Aphid-Borne Yellows Virus Isolated from Pumpkins

Pathogens ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 53
Author(s):  
Vivek Khanal ◽  
Harrington Wells ◽  
Akhtar Ali
Keyword(s):  
Phylogenetic Analysis ◽  
Mosaic Virus ◽  
Zucchini Yellow Mosaic Virus ◽  
Yellow Mosaic Virus ◽  
Watermelon Mosaic Virus ◽  
High Prevalence ◽  
The Us ◽  
Close Relationship ◽  
The Status ◽  
Low Incidence

Field information about viruses infecting crops is fundamental for understanding the severity of the effects they cause in plants. To determine the status of cucurbit viruses, surveys were conducted for three consecutive years (2016–2018) in different agricultural districts of Oklahoma. A total of 1331 leaf samples from >90 fields were randomly collected from both symptomatic and asymptomatic cucurbit plants across 11 counties. All samples were tested with the dot-immunobinding assay (DIBA) against the antisera of 10 known viruses. Samples infected with papaya ringspot virus (PRSV-W), watermelon mosaic virus (WMV), zucchini yellow mosaic virus (ZYMV), and cucurbit aphid-borne-yellows virus (CABYV) were also tested by RT-PCR. Of the 10 viruses, PRSV-W was the most widespread, with an overall prevalence of 59.1%, present in all 11 counties, followed by ZYMV (27.6%), in 10 counties, and WMV (20.7%), in seven counties, while the remaining viruses were present sporadically with low incidence. Approximately 42% of the infected samples were positive, with more than one virus indicating a high proportion of mixed infections. CABYV was detected for the first time in Oklahoma, and the phylogenetic analysis of the first complete genome sequence of a CABYV isolate (BL-4) from the US showed a close relationship with Asian isolates.

Final stage larvae and puparia of Platypezidae (Diptera)

2004 ◽  
Vol 35 (1) ◽  
pp. 79-105 ◽  
Author(s):  
Peter Chandler ◽  
Francis Gilbert ◽  
Graham Rotheray
Keyword(s):  
Phylogenetic Analysis ◽  
Final Stage ◽  
Abdominal Segment ◽  
Early Stage ◽  
Dorsal Surface ◽  
Uniform Pattern ◽  
Thoracic And Abdominal ◽  
Head Skeleton ◽  
Basal Position

AbstractPlatypezidae occupy an important basal position within the Muscomorpha. However, morphological analyses of larval Platypezidae are incomplete and early stage data is insufficient to inform phylogenetic analysis and recognition of groundplan characters and states within Muscomorpha. For example, knowledge is poor of the characters of respiratory organs, head, head skeleton, thorax and segmental sensilla. In this study we describe and compare these features of 16 species in 11 genera. The head appears as a distinct fleshy organ with atrium and antennae and maxillary organs separated on the dorsal surface. Head skeletons are characterised by an anteriorly projecting labrum and labium with laterally placed mandibles. The prothorax is frequently armoured with sclerotised regions and spicules. A repeated and uniform pattern of up to 11 pairs of sensilla circumvent each thoracic and abdominal segment. Respiratory organs vary little in size and arrangement of spiracular openings. Using a set of 43 larval and puparial characters and based on a Brachyceran outgroup, a sequence of genera is established which places Melanderomyia as the most basal. These results are compared with estimates of phylogeny based on adult characters.

Pattern and process in the evolution of the Odontopleuridae (Trilobita). The Selenopeltinae and Ceratocephalinae

1991 ◽  
Vol 82 (2) ◽  
pp. 143-181 ◽  
Author(s):  
Lars Ramsköld
Keyword(s):  
Phylogenetic Tree ◽  
Type Species ◽  
Anterior Part ◽  
Cladistic Analysis ◽  
Sister Taxon ◽  
New Genera ◽  
Pattern And Process ◽  
Single Character ◽  
Close Relationship ◽  
Subjective Synonym

ABSTRACTThe systematics of parts of the Odontopleuridae are revised using character analyses tracing homologous structures, and a computerised cladistic analysis. The choice of outgroup is shown to affect the result of the analysis. Several synapomorphies place Selenopeltis, the type genus of the Selenopeltinae Hawle & Corda, 1847 as sister genus to Dicranurus. The latter's close relationship to Miraspis, type genus of the Miraspidinae Richter & Richter, 1917 is confirmed. The Selenopeltinae therefore becomes a senior subjective synonym of the Miraspidinae. The Selenopeltinae includes about 90 of the over 380 named odontopleurid species known to date (excluding accepted synonyms). The Ceratocephalinae is recognised, including about 30 species. The paired, large pygidial border spines present in most odontopleurids are in some species not homologous, and a falsifiable hypothesis is proposed for the homology of the ‘true major border spines’. This structure is the posterior pleural spine of the tenth postcephalic segment in selenopeltines, ceratocephalines and odontopleurines, and in acidaspidines and apianurines it is the serially homologous spine of the eleventh postcephalic segment. The spine belongs to the first pygidial segment in all taxa except ceratocephalines, where it is on the last thoracic segment. The homology in selenopeltines of the progressive restructuring of the cheek border is reviewed, explaining the supramarginal appearance of the genal spine. The presence and homology of the sublobation of L1 in odontopleurids is discussed, and it may be homologous with the sublobation in lichids. The strongly differentiated thoracic segmental lengths (exsag.), with maximum length reached in the anterior part of thorax, and the much reduced length of the posterior segments, are aspects of a single character-complex, uniquely derived within the Selenopeltinae. The ontogenetic origin of the anterior and posterior pleural spines is reviewed. The presence in Ceratocephala of two instars in one meraspid degree is discussed. A cladistic analysis of selenopeltine and ceratocephaline genera does not entirely resolve the topology of the phylogenetic tree of these taxa, but it confirms Selenopeltis as sister taxon to Dicranurus. These two genera belong in a clade also including Miraspis, Selenopeltoides, and Ceratonurus. Two new genera are erected, Ceratocara and Archaeopleura, the latter with type species A. kazakhensis sp. nov.

A new species of Scrophularia (Scrophulariaceae) from Hubei, China

Phytotaxa ◽  
2018 ◽  
Vol 350 (1) ◽  
pp. 1
Author(s):  
RUI-HONG WANG ◽  
MAO-QIN XIA ◽  
JIN-BO TAN ◽  
CHUAN CHEN ◽  
XIN-JIE JIN ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Species Delimitation ◽  
Morphological Characters ◽  
Central China ◽  
Molecular Phylogenetic Analysis ◽  
Leaf Margin ◽  
Close Relationship ◽  
Molecular Phylogenetic ◽  
A New Species

A new species, Scrophularia jinii (Scrophulariaceae), from Central China is described and illustrated. This new species was formerly misidentified as S. fargesii, from which it differs in many morphological characters. Moreover, it is distinct with all known Scrophularia species in its unique deeply double serrate leaf margin with 3–7 big teeth on each side. Molecular phylogenetic analysis further supports its species delimitation and suggests a close relationship with several Japanese and North American species.

Ichthyosaurs from the Upper Triassic (Carnian–Norian) of the New Siberian Islands, Russian Arctic, and their implications for the evolution of the ichthyosaurian basicranium and vertebral column

2021 ◽  
pp. 1-24
Author(s):  
Nikolay G. ZVERKOV ◽  
Dmitry V. GRIGORIEV ◽  
Andrzej S. WOLNIEWICZ ◽  
Alexey G. KONSTANTINOV ◽  
Evgeny S. SOBOLEV
Keyword(s):  
Vertebral Column ◽  
Cervical Vertebrae ◽  
Upper Triassic ◽  
Late Triassic ◽  
Phylogenetic Position ◽  
New Taxon ◽  
Russian Arctic ◽  
Micro Computed Tomography ◽  
New Siberian Islands ◽  
Group Relationships

ABSTRACT The first ichthyosaurian specimens discovered from the Upper Triassic of the Russian Arctic (Kotelny Island, New Siberian Islands) are described herein. They include the remains of large- to small-bodied ichthyosaurians originating from six stratigraphic levels spanning the lower Carnian to middle Norian. The material is mostly represented by isolated vertebrae and ribs, which are not possible to accurately diagnose, but also includes specimens comprising associated vertebrae and a fragmentary skeleton that preserves cranial remains (parabasisphenoid, fragmentary quadrate, partial mandible and hyoids). Based on vertebral and rib morphology, we identify the specimens as representatives of the following taxonomic groups: large-bodied shastasaurids, medium-sized indeterminate ichthyosaurians with a single rib facet in the presacral centra, and small euichthyosaurians with double rib facets present throughout the presacral vertebrae that likely represent toretocnemids and/or basal parvipelvians. In addition, the cranial and mandibular remains preserved in one of the specimens, ZIN PH 5/250, were studied using micro-computed tomography. Its mandible is highly similar to that of toretocnemids, whereas the parabasisphenoid demonstrates a peculiar combination of both plesiomorphic and derived character states, providing the first detailed data on this cranial element in a Late Triassic ichthyosaurian. Furthermore, the specimen also demonstrates a distinctive condition of rib articulation in the anteriormost presacral (cervical) vertebrae, which together with other features allows for the erection of a new taxon – Auroroborealia incognita gen. et sp. nov. Although the phylogenetic position of this taxon is uncertain due to its fragmentary nature, its anatomy, indicating toretocnemid or parvipelvian affinities, further supports the previously hypothesised sister-group relationships between these two clades. The morphology of the parabasisphenoid and vertebral column of the new taxon is discussed in broader contexts of the patterns of evolution of these skeletal regions in ichthyosaurs.

The face and superficial neck

2013 ◽  
Author(s):  
Martin E. Atkinson
Keyword(s):  
Vertebral Column ◽  
Cervical Vertebrae ◽  
Small Body ◽  
Spinous Process ◽  
Odontoid Process ◽  
Cervical Vertebra ◽  
Intervertebral Discs ◽  
The Body ◽  
Thoracic Vertebrae ◽  
The Face

The surface anatomies of the face and neck and their supporting structures that can be palpated have been described in Chapter 20. It is now time to move to the structures that lie under the skin but which cannot be identified by touch starting with the neck and moving up on to the face and scalp. The cervical vertebral column comprises the seven cervical vertebrae and the intervening intervertebral discs. These have the same basic structure as the thoracic vertebrae described in Section 10.1.1. Examine the features of the cervical vertebra shown in Figure 23.1 and compare it with the thoracic vertebra shown in Figure 10.3. You will see that cervical vertebrae have a small body and a large vertebral foramen. They also have two distinguishing features, a bifid spinous process and a transverse foramen, piercing each transverse process; the vertebral vessels travel through these foramina. The first and second vertebrae are modified. The first vertebra, the atlas, has no body. Instead, it has two lateral masses connected by anterior and posterior arches. The lateral masses have concave superior facets which articulate with the occipital condyles where nodding movements of the head take place at the atlanto-occipital joints. The second cervical vertebra, the axis, has a strong odontoid process (or dens because of its supposed resemblance to a tooth) projecting upwards from its body. This process is, in fact, the body of the first vertebra which has fused with the body of the axis instead of being incorporated into the atlas. The front of the dens articulates with the back of the anterior arch of the atlas; rotary (shaking) movements of the head occur at this joint. The seventh cervical vertebra has a very long spinous process which is easily palpable. The primary curvature of the vertebral column is concave forwards and this persists in the thoracic and pelvic regions. In contrast, the cervical and lumbar parts of the vertebral column are convexly curved anteriorly. These anterior curvatures are secondary curvatures which appear in late fetal life. The cervical curvature becomes accentuated in early childhood as the child begins to support its own head and the lumbar curve develops as the child begins to sit up.

The locomotor system

2013 ◽  
Author(s):  
Martin E. Atkinson
Keyword(s):  
Vertebral Column ◽  
Cervical Vertebrae ◽  
Lumbar Vertebrae ◽  
Posterior Wall ◽  
Axial Skeleton ◽  
Intervertebral Discs ◽  
Central Canal ◽  
The Body ◽  
Thoracic Vertebrae ◽  
Locomotor System

The locomotor system comprises the skeleton, composed principally of bone and cartilage, the joints between them, and the muscles which move bones at joints. The skeleton forms a supporting framework for the body and provides the levers to which the muscles are attached to produce movement of parts of the body in relation to each other or movement of the body as a whole in relation to its environment. The skeleton also plays a crucial role in the protection of internal organs. The skeleton is shown in outline in Figure 2.1A. The skull, vertebral column, and ribs together constitute the axial skeleton. This forms, as its name implies, the axis of the body. The skull houses and protects the brain and the eyes and ears; the anatomy of the skull is absolutely fundamental to the understanding of the structure of the head and is covered in detail in Section 4. The vertebral column surrounds and protects the spinal cord which is enclosed in the spinal canal formed by a large central canal in each vertebra. The vertebral column is formed from 33 individual bones although some of these become fused together. The vertebral column and its component bones are shown from the side in Figure 2.1B. There are seven cervical vertebrae in the neck, twelve thoracic vertebrae in the posterior wall of the thorax, five lumbar vertebrae in the small of the back, five fused sacral vertebrae in the pelvis, and four coccygeal vertebrae—the vestigial remnants of a tail. Intervertebral discs separate individual vertebrae from each other and act as a cushion between the adjacent bones; the discs are absent from the fused sacral vertebrae. The cervical vertebrae are small and very mobile, allowing an extensive range of neck movements and hence changes in head position. The first two cervical vertebrae, the atlas and axis, have unusual shapes and specialized joints that allow nodding and shaking movements of the head on the neck. The thoracic vertebrae are relatively immobile. combination of thoracic vertebral column, ribs, and sternum form the thoracic cage that protects the thoracic organs, the heart, and lungs and is intimately involved in ventilation (breathing).

scholarly journals The postcranial skeleton of Vagaceratops irvinensis (Dinosauria, Ceratopsidae)

2014 ◽  
Vol 1 ◽  
pp. 1 ◽  
Author(s):  
Robert B Holmes
Keyword(s):  
Latissimus Dorsi ◽  
Vertebral Column ◽  
Cervical Vertebrae ◽  
Dorsal Surface ◽  
Ventral Surface ◽  
Advanced Age ◽  
Time Of Death ◽  
Postcranial Skeleton ◽  
Hind Limbs ◽  
Left Front

The postcranial skeleton of Vagaceratops (= Chasmosaurus) irvinensis (CMN 41357), lacking only the tail, most of the left front and left hind limbs, and portions of the pelvis, is preserved in articulation. It is one of the most complete, best articulated ceratopsid skeletons known. Both the manus and vertebral column exhibit conspicuous pathologies, possibly an indication of advanced age at the time of death. The vertebral column comprises a syncervical, six additional cervical vertebrae, and 12 dorsals. A partial synsacrum is represented by two dorsosacrals, four sacrals, two caudosacrals, and a partial third caudosacral centrum. The ribcage, although crushed, is nearly complete. The sternum is unusually wide compared with other ceratopsids. As in other chasmosaurines, the humerus bears a prominent deltopectoral crest that forms the anterior edge of the broad, rectangular proximal humeral expansion. The medial tuberosity is separated from the dorsal surface of the humerus by a distinct notch. The insertion for the latissimus dorsi is conspicuous. The deltopectoral crest extends a full half of the distance to the distal end of the humerus. Epipodials of the forelimb are relatively short compared to the corresponding propodial. The ulna has a long, distinctly triangular olecranon, broadly rounded anterolateral process, prominent medial process, and a deeply concave trochlear notch. The terminal phalanges on the fourth and fifth manual digits are relatively large, and unlike other ceratopsids have distinct distal ?articular facets. The fourth trochanter of the femur is relatively proximal in position. This study and other recent studies of ceratopsid postcrania suggest that potentially useful taxonomic variation is present in the number of dorsosacrals, size of the groove on the ventral surface of the sacrum, morphology of the last dorsal and dorsosacral ribs, morphology of the scapula and proximal expansion of the humerus, morphology of the ulna, ratio of humerus/epipodium, morphology of the fifth manual digit, and position of the fourth trochanter of the femur.

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