Ptychodus
 Ptychodus mortoni  | |
| Tacsanomaíocht | |
|---|---|
| For-ríocht | Eukaryota |
| Ríocht | Animalia |
| Fíleam | Chordata |
| Aicme | Chondrichthyes |
| Fine | Ptychodontidae |
| Géineas | Ptychodus L. Agassiz, 1837 |
Is éard is Ptychodus (ón Gréigis: πτυχή ptyche ‘filleadh’ agus Gréigis: ὀδούς odoús ‘fiacail’) [1] ann ná géineas de shiorcanna cruafhagach (durophagous) atá imithe in éag (blaosc-bhrú) ón Chailceach Déanach. [2] [3] Faightear iontaisí fiacla Ptychodus i go leor dríodar muirí ón gCréiteach Déanach ar fud an domhain. [3] Rinneadh cur síos ar go leor speiceas. Tá na hiarsmaí is óige thart ar 85 milliún bliain d'aois. Fuarthas líon mór iarsmaí san Muir Intíre Thiar (Western Interior Seaway). [2] Fuarthas amach i bhfoilseachán 2016 gur dóichí gur fhíorsiorcanna iad Ptychodus a bhaineann le Selachimorpha, seachas Hybodontiformes nó Batoidea mar a measadh roimhe seo. [4] [5] Baineadh de thátal as staidéar in 2024 ar chnámharlach iomlán gur leis na Lamniformes iad. [6] Tagann stair a mbeatha i gcomhthráth le gnáthshaol go leor siorcanna móra eile: bhí saol sách fada acu agus d'fhás siad go mall agus rug siad sliocht mór agus álta beaga. [7]
Tagairtí[cuir in eagar | athraigh foinse]
- ↑ Roberts (1839). "An etymological and explanatory dictionary of the terms and language of geology" (in English). London: Longman, Orme, Brown, Green, & Longmans. Dáta rochtana: 31 December 2021.
- ↑ 2.0 2.1 Everhart. “Ptychodus mortoni”. Ocean of Kansas.
- ↑ 3.0 3.1 The paleobioloy Database Ptychodus entry Curtha i gcartlann 2013-07-26 ar an Wayback Machine accessed on 8/23/09
- ↑ Everhart. "An associated dentition and calcified vertebral centra of the Late Cretaceous elasmobranch, Ptychodus anonymus Williston 1900" 4 (4): 125–136.
- ↑ Hoffman (July 2016). "Scanning electron microscope examination of the dental enameloid of the Cretaceous durophagous shark Ptychodus supports neoselachian classification". Journal of Paleontology 90 (4): 741–762. doi:. Bibcode: 2016JPal...90..741H.
- ↑ Starr (2024-04-23). “Stunning Remains of Great White Shark's Giant Ancestors Reveal a Surprising Diet” (en-US). ScienceAlert. Dáta rochtana: 2024-04-24.
- ↑ Jambura (2020-04-22). "Articulated remains of the extinct shark Ptychodus (Elasmobranchii, Ptychodontidae) from the Upper Cretaceous of Spain provide insights into gigantism, growth rate and life history of ptychodontid sharks" (as en). PLOS ONE 15 (4): e0231544. doi:. ISSN 1932-6203. PMID 32320430. Bibcode: 2020PLoSO..1531544J.