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H. V. Sheverdyukova - One of the best experts on this subject based on the ideXlab platform.
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Early stages of skull embryogenesis in the Grass snake, Natrix natrix (Serpentes, Colubridae)
Russian Journal of Developmental Biology, 2015Co-Authors: M. F. Kovtun, H. V. SheverdyukovaAbstract:Studies of previous authors on snake skull embryogenesis have been performed on embryos obtained from eggs after oviposition. The aim of this study was to investigate the initial stages of chondrocra-nium development in Grass snake Natrix natrix Linnaeus, 1758, embryos before oviposition. Natrix natrix embryos at early developmental stages (24–27 according to the table of normal development by D. Zehr (1962)) were obtained by means of caesarean section. At developmental stages 25–27, previously undescribed structures were found in the region of future skull formation. These structures exist during one or two stages and then disappear. Therefore, we call them “temporary structures.” The assumption about the nature of these structures is based on their topography and comparison with the structures of developing or fully formed Chondrocranium in other vertebrates. It is hypothesized that the temporary structures in Natrix natrix chon-drocranium are vestiges of primary Chondrocranium of ancestral vertebrate forms, and they indicate the exist-ence of several variants in the formation of Chondrocranium in the historical vertebrates’ development.
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Polar cartilages and formation of Crista sellaris in grass snake, natrix natrix (Ophidia, Colubridae), Chondrocranium at the early stages of embryogenesis
Vestnik Zoologii, 2012Co-Authors: H. V. SheverdyukovaAbstract:Polar Cartilages and Formation of Crista Sellaris in Grass Snake, Natrix natrix (Ophidia, Colubridae), Chondrocranium at the Early Stages of Embryogenesis. Sheverdyukova H. V. – The initial developmental stages of grass snake’s, Natrix natrix Linnaeus, 1758 Chondrocranium are described. Three paired structures form the floor of N. natrix’s neurocranium: cranial trabeculae, polar cartilages, and parachordals. The primordiums of polar cartilages and their independent centers of chondrification are identified at the stage 26 of development for the first time for N. natrix and snakes in general. The participation of these structures in the formation of crista sellaris and carotid foramina is proved. Iieyðiua oðyue e oiðieðiâaiea crista sellaris â oðyuaâii ÷aðaia oaea iaueiiâaiiiai, Natrix natrix (Ophidia, Colubridae), ia ðaiieo noaaeyo ýiaðeiaaiaca. Oaâaðaþeiâa A. Â. – Iienaiu ia÷aeuiua ýoaiu ðacâeoey oðyuaâiai ÷aðaia Natrix natrix Linnaeus, 1758. Oðe iaðiua noðoeooðu: ÷aðaiiua oðaaaeoeu, iieyðiua oðyue e iaðaoiðaaeee iaðacoþo aii iaeðieðaieoia N. natrix. Ca÷aoee iieyðiuo oðyuae e eo iacaâeneiua oaioðu ioðyuaâaiey iiðaaaeaiu ia 26-e noaaee ðacâeoey âiaðâua aey N. natrix e ciae â oaeii. Aieacaii o÷anoea ýoeo noðoeooð â oiðieðiâaiee crista sellaris e niiiuo ioâaðnoee. Eeþ÷aâua neiâa :iieyðiua oðyue, crista sellaris, niiiua ioâaðnoey, ýiaðeiiaeuiia ðacâeoea, oðyuaâie ÷aðai, Natrix natrix.
A D Elster - One of the best experts on this subject based on the ideXlab platform.
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Suture closure in the human Chondrocranium: CT assessment.
Radiology, 1995Co-Authors: L A Madeline, A D ElsterAbstract:PURPOSE: To chronicle the development of ossification centers, sutures, and synchondroses in the Chondrocranium throughout childhood by using computed tomography (CT). MATERIALS AND METHODS: One hundred eighty-nine children (age range, newborn to 18 years; median age, 4.0 years) without skull base deformity were referred for cranial CT. The closure of 18 sutures and synchondroses was graded. RESULTS: In the occipital bone at birth, six components were identified. The Kerckring ossicle rapidly fused to the supraoccipital bone within the 1st month. At age 1-3 years, the posterior and anterior intraoccipital synchondroses began to fuse. The occipitomastoidal, petro-occipital, and spheno-occipital synchondroses remained partially open into the teenage years. In the sphenoid bone at birth, 13 ossification centers were identified; most assimilated into the sphenoidal body during the first 2 years. Pneumatization of the sphenoid sinus appeared at age 1-2 years and advanced posteriorly over the next 3-5 years. CO...
Luiz Norberto Weber - One of the best experts on this subject based on the ideXlab platform.
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Comparative analysis of the Chondrocranium and hyobranchial skeleton of bromeliad arboreal frog larvae of the genus Phyllodytes Wagler, 1830 (Anura, Hylidae)
Zootaxa, 2020Co-Authors: Patrícia Souza Da Mota, Marianna Isabella Rosa Rodrigues De Oliv, Marcelo Felgueiras Napoli, Luiz Norberto WeberAbstract:The genus Phyllodytes comprises 15 species, ten of them having their tadpole external morphology described in the literature. However, there are few descriptive studies on Chondrocranium and hyobranchial skeleton. In this work, we describe the Chondrocranium and hyobranchial skeleton of Phyllodytes larvae and discuss shared features and interspecific variation. Our findings suggest that the skeletal morphology is mostly conserved in the genus, with common features including a single suprarostral cartilage, short infrarostral cartilages, and overall short trabecular horns. Main intrageneric variations include the arrangement of the ascending process, the presence of larval otic process, and the configuration of the crista parotica. These variations are not correlated with the phylogenetic structure of the genus. Some distinctive aspects of P. praeceptor and P. gyrinaethes are also described in tadpoles of Osteopilus ocellatus, and could be related to oophagous habits in these tadpoles.
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Description of the Tadpole of Pseudopaludicola canga Giaretta and Kokubum, 2003 (Anura: Leptodactylidae)
South American Journal of Herpetology, 2018Co-Authors: Etielle B. Andrade, Johnny Sousa Ferreira, André Masahide Guimarães Takazone, Anna Evelin Coimbra Libório, Luiz Norberto WeberAbstract:We describe the external morphology, internal oral anatomy, and Chondrocranium of Pseudopaludicola canga. The tadpole is diagnosed by the following combined characters: elliptic body, reniform nostril, dorsal fin starting at the body-tail junction and labial tooth row formula 2(2)/2(1) presenting two lateral gaps in the marginal papillae of the lower lip. Regarding the oral cavity, there is a pattern similarity in some characters among the three species of the genus for which the structure has been described; however, P. canga can be characterized by having a pair of infralabial papillae, irregular median ridge, three lingual papillae, fewer papillae in the buccal roof arena, and greater number of papillae in the buccal floor. The Chondrocranium of P. canga differs from that of P. boliviana by presenting a distal connection between the pars alaris and pars corporis of the cartilago suprarostralis; and differs from P. falcipes by lacking a processus pseudopterygoideus. Further, our data emphasize the utility of larval characters as additional tools in the diagnosis of species within this genus.
L A Madeline - One of the best experts on this subject based on the ideXlab platform.
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Suture closure in the human Chondrocranium: CT assessment.
Radiology, 1995Co-Authors: L A Madeline, A D ElsterAbstract:PURPOSE: To chronicle the development of ossification centers, sutures, and synchondroses in the Chondrocranium throughout childhood by using computed tomography (CT). MATERIALS AND METHODS: One hundred eighty-nine children (age range, newborn to 18 years; median age, 4.0 years) without skull base deformity were referred for cranial CT. The closure of 18 sutures and synchondroses was graded. RESULTS: In the occipital bone at birth, six components were identified. The Kerckring ossicle rapidly fused to the supraoccipital bone within the 1st month. At age 1-3 years, the posterior and anterior intraoccipital synchondroses began to fuse. The occipitomastoidal, petro-occipital, and spheno-occipital synchondroses remained partially open into the teenage years. In the sphenoid bone at birth, 13 ossification centers were identified; most assimilated into the sphenoidal body during the first 2 years. Pneumatization of the sphenoid sinus appeared at age 1-2 years and advanced posteriorly over the next 3-5 years. CO...
Dennis Rödder - One of the best experts on this subject based on the ideXlab platform.
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Anatomical measurements.
2017Co-Authors: Markus Krings, Benjamin Klein, Markus J. Heneka, Dennis RödderAbstract:(A) Chondrocranium and frontoparietalia of R. amazonica in a dorsal view. Length and width of the frontoparietalia are marked by green double arrows, length and width of the Chondrocranium (without palatoquadratum) are marked by black double arrows. (B) Chondrocranium (blue), m. suspensorioangularis (red) and m. hyoangularis (yellow) of R. imitator in a lateral view. The length of the m. hyoangularis is marked by a black double arrow. The part running without association to the m. suspensorioangularis is marked by a green double arrow. (C) Dissection of R. amazonica in a ventral view, scale bar 1mm. The visible part of the liver at the widest point of the inner organs is marked by a green double arrow. The complete width of all inner organs at this point is marked by a black double arrow.
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Larval Chondrocranium of Ranitomeya vanzolinii.
2017Co-Authors: Markus Krings, Benjamin Klein, Markus J. Heneka, Dennis RödderAbstract:(A) Ventral view, ossifications shown in red, cartilage in blue. (B) Dorsal view, ossifications shown in red, cartilage in blue. (C) Dorsal view, cleared and stained specimen (cranium and backbone only), ossifications stained red, cartilage blue, scale bar 1mm. Limbs and girdles were lost during clearing. (D) Hyobranchial apparatus. (E) Lateral view. A, B, D and E were reconstructed from ZFMK 97369. C shows ZFMK 97379. All tadpoles used were in Gosner stage 41. bb: basibranchiale, ca: capsula auditiva, cb: ceratobranchialia, ch: ceratohyale, ci: cartilago infrarostralis, cm: cartilago meckeli, cot: commissurae terminales, cpq: curvatura posterior quadrati, cs: cartilago suprarostralis, ct: cornu trabeculae, eo: exoccipitale, fp: frontoparietale, pa: pars alaris, pao: processus antorbitalis, ph: planum hypobranchiale, pm: processus muscularis, pq: palatoquadratum, pr: pars reuniens, ps: parasphenoid, pta: planum trabeculae anticum, tc: trabecula cranii, ts: tectum synoticum.
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Chondrocranial muscles of Ranitomeya amazonica.
2017Co-Authors: Markus Krings, Benjamin Klein, Markus J. Heneka, Dennis RödderAbstract:The Chondrocranium (blue) is shown in a dorsal view with all cranial muscles. The reconstruction was done from a stage 41 tadpole (ZFMK 97366). For further information on the muscles we provide a 3D pdf in S3 3D pdf. In this model all muscles can be added to or removed from the scene by a checkbox. The model is rotatable and can be seen in all perspectives.
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Chondrocranial muscles of Ranitomeya benedicta.
2017Co-Authors: Markus Krings, Benjamin Klein, Markus J. Heneka, Dennis RödderAbstract:The Chondrocranium (blue) is shown in a dorsal view with all cranial muscles. The reconstruction was done from a stage 41 tadpole (ZFMK 97367). For further information on the muscles we provide a 3D pdf in S4 3D pdf. In this model all muscles can be added to or removed from the scene by a checkbox. The model is rotatable and can be seen in all perspectives.
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Chondrocranial muscles of Ranitomeya vanzolini.
2017Co-Authors: Markus Krings, Benjamin Klein, Markus J. Heneka, Dennis RödderAbstract:The Chondrocranium (blue) is shown in a dorsal view with all cranial muscles. The reconstruction was done from a stage 41 tadpole (ZFMK 97369). For further information on the muscles we provide a 3D pdf in S1 3D pdf. In this model all muscles can be added to or removed from the scene by a checkbox. The model is rotatable and can be seen in all perspectives.