Mineralization of the Callorhinchus Vertebral Column (Holocephali; Chondrichthyes)
Members of the Chondrichthyes (Elasmobranchii and Holocephali) are distinguished by their largely cartilaginous endoskeletons, which comprise an uncalcified core overlain by a mineralized layer; in the Elasmobranchii (sharks, skates, rays) most of this mineralization takes the form of calcified poly...
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| Format: | Journal Article |
| Language: | English |
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FRONTIERS MEDIA SA
2020
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| Online Access: | http://purl.org/au-research/grants/arc/LE130100053 http://hdl.handle.net/20.500.11937/87689 |
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| author | Pears, Jacob B. Johanson, Z. Trinajstic, Kate Dean, M.N. Boisvert, Catherine |
| author_facet | Pears, Jacob B. Johanson, Z. Trinajstic, Kate Dean, M.N. Boisvert, Catherine |
| author_sort | Pears, Jacob B. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Members of the Chondrichthyes (Elasmobranchii and Holocephali) are distinguished by their largely cartilaginous endoskeletons, which comprise an uncalcified core overlain by a mineralized layer; in the Elasmobranchii (sharks, skates, rays) most of this mineralization takes the form of calcified polygonal tiles known as tesserae. In recent years, these skeletal tissues have been described in ever increasing detail in sharks and rays, but those of Holocephali (chimaeroids) have been less well-studied, with conflicting accounts as to whether or not tesserae are present. During embryonic ontogeny in holocephalans, cervical vertebrae fuse to form a structure called the synarcual. The synarcual mineralizes early and progressively, anteroposteriorly and dorsoventrally, and therefore presents a good skeletal structure in which to observe mineralized tissues in this group. Here, we describe the development and mineralization of the synarcual in an adult and stage 36 elephant shark embryo (Callorhinchus milii). Small, discrete, but irregular blocks of cortical mineralization are present in stage 36, similar to what has been described recently in embryos of other chimaeroid taxa such as Hydrolagus, while in Callorhinchus adults, the blocks of mineralization are more irregular, but remain small. This differs from fossil members of the holocephalan crown group (Edaphodon), as well as from stem group holocephalans (e.g., Symmorida, Helodus, Iniopterygiformes), where tesserae are notably larger than in Callorhinchus and show similarities to elasmobranch tesserae, for example with respect to polygonal shape. |
| first_indexed | 2025-11-14T11:27:14Z |
| format | Journal Article |
| id | curtin-20.500.11937-87689 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T11:27:14Z |
| publishDate | 2020 |
| publisher | FRONTIERS MEDIA SA |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-876892022-03-03T02:27:55Z Mineralization of the Callorhinchus Vertebral Column (Holocephali; Chondrichthyes) Pears, Jacob B. Johanson, Z. Trinajstic, Kate Dean, M.N. Boisvert, Catherine Science & Technology Life Sciences & Biomedicine Genetics & Heredity Holocephali Callorhinchus tesserae mineralization evolution stem group Holocephali TESSELLATED SKELETON CALCIFIED CARTILAGE SHARKS CALCIFICATION EVOLUTION FEATURES DOGFISH ORIGIN GROWTH FISH Members of the Chondrichthyes (Elasmobranchii and Holocephali) are distinguished by their largely cartilaginous endoskeletons, which comprise an uncalcified core overlain by a mineralized layer; in the Elasmobranchii (sharks, skates, rays) most of this mineralization takes the form of calcified polygonal tiles known as tesserae. In recent years, these skeletal tissues have been described in ever increasing detail in sharks and rays, but those of Holocephali (chimaeroids) have been less well-studied, with conflicting accounts as to whether or not tesserae are present. During embryonic ontogeny in holocephalans, cervical vertebrae fuse to form a structure called the synarcual. The synarcual mineralizes early and progressively, anteroposteriorly and dorsoventrally, and therefore presents a good skeletal structure in which to observe mineralized tissues in this group. Here, we describe the development and mineralization of the synarcual in an adult and stage 36 elephant shark embryo (Callorhinchus milii). Small, discrete, but irregular blocks of cortical mineralization are present in stage 36, similar to what has been described recently in embryos of other chimaeroid taxa such as Hydrolagus, while in Callorhinchus adults, the blocks of mineralization are more irregular, but remain small. This differs from fossil members of the holocephalan crown group (Edaphodon), as well as from stem group holocephalans (e.g., Symmorida, Helodus, Iniopterygiformes), where tesserae are notably larger than in Callorhinchus and show similarities to elasmobranch tesserae, for example with respect to polygonal shape. 2020 Journal Article http://hdl.handle.net/20.500.11937/87689 10.3389/fgene.2020.571694 English http://purl.org/au-research/grants/arc/LE130100053 http://creativecommons.org/licenses/by/4.0/ FRONTIERS MEDIA SA fulltext |
| spellingShingle | Science & Technology Life Sciences & Biomedicine Genetics & Heredity Holocephali Callorhinchus tesserae mineralization evolution stem group Holocephali TESSELLATED SKELETON CALCIFIED CARTILAGE SHARKS CALCIFICATION EVOLUTION FEATURES DOGFISH ORIGIN GROWTH FISH Pears, Jacob B. Johanson, Z. Trinajstic, Kate Dean, M.N. Boisvert, Catherine Mineralization of the Callorhinchus Vertebral Column (Holocephali; Chondrichthyes) |
| title | Mineralization of the Callorhinchus Vertebral Column (Holocephali; Chondrichthyes) |
| title_full | Mineralization of the Callorhinchus Vertebral Column (Holocephali; Chondrichthyes) |
| title_fullStr | Mineralization of the Callorhinchus Vertebral Column (Holocephali; Chondrichthyes) |
| title_full_unstemmed | Mineralization of the Callorhinchus Vertebral Column (Holocephali; Chondrichthyes) |
| title_short | Mineralization of the Callorhinchus Vertebral Column (Holocephali; Chondrichthyes) |
| title_sort | mineralization of the callorhinchus vertebral column (holocephali; chondrichthyes) |
| topic | Science & Technology Life Sciences & Biomedicine Genetics & Heredity Holocephali Callorhinchus tesserae mineralization evolution stem group Holocephali TESSELLATED SKELETON CALCIFIED CARTILAGE SHARKS CALCIFICATION EVOLUTION FEATURES DOGFISH ORIGIN GROWTH FISH |
| url | http://purl.org/au-research/grants/arc/LE130100053 http://hdl.handle.net/20.500.11937/87689 |