{"id":468,"date":"2025-12-01T22:05:04","date_gmt":"2025-12-01T20:05:04","guid":{"rendered":"https:\/\/blogs.ua.es\/messinianalicante\/?p=468"},"modified":"2025-12-01T22:05:04","modified_gmt":"2025-12-01T20:05:04","slug":"evolution-of-neogene-fossil-ceratoliths-coccolithophores-by-duplication","status":"publish","type":"post","link":"https:\/\/blogs.ua.es\/messinianalicante\/2025\/12\/01\/evolution-of-neogene-fossil-ceratoliths-coccolithophores-by-duplication\/","title":{"rendered":"Evolution of Neogene fossil ceratoliths (Coccolithophores) by duplication"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">The calcareous nannofossils of the genus&nbsp;<em>Ceratolithus<\/em>, known for their horseshoe shape (referred to as ceratolith), evolved from the&nbsp;<em>Orthorhabdus rugosus<\/em>, a rod-shape nannolith with three rodded blades (sinistral, median, and dextral). The sinistral and median blades gave rise to the sinistral and dextral arms of the ceratolith, while the dextral blade was reduced to a keel. The first species of the&nbsp;<em>Ceratolithus<\/em>&nbsp;genus branch is&nbsp;<em>Ceratolithus finifer<\/em>, which rapidly evolved into&nbsp;<em>Ceratolithus acutus<\/em>. Around at the same time, the merging of three duplicated, delicate horseshoe-shaped structures derived from&nbsp;<em>C. finifer<\/em>&nbsp;&#8211; two equivalent and one a mirror image of the other- resulted in the short-lived&nbsp;<em>Poralithus atlanticus<\/em>&nbsp;(5.32 to 5.17&nbsp;Ma). Later on, two duplicated horseshoe-shaped structures oriented at an angle of approximately 45\u00b0 and fused at the horseshoe&#8217;s close side, produced&nbsp;<em>Amaurolithus tricorniculatus<\/em>&nbsp;(5.30 to 4.86&nbsp;Ma). The crystallographic features of&nbsp;<em>A. tricorniculatus<\/em>&nbsp;points to a possible origin by two duplicated&nbsp;<em>Ceratolithus<\/em>-type horseshoes (birefringent in its stable layout) and derived from&nbsp;<em>C. finifer<\/em>. Being the type species of the&nbsp;<em>Amaurolithus<\/em>&nbsp;genus and also evolving from the&nbsp;<em>Ceratolithus<\/em>&nbsp;branch, then the early \u2018<em>Amaurolithus<\/em>\u2019, which evolved from&nbsp;<em>O. rugosus,<\/em>&nbsp;have been placed in a newly defined&nbsp;<em>Protoamaurolithus<\/em>&nbsp;genus, as&nbsp;<em>Protoamaurolithus primus<\/em>&nbsp;and&nbsp;<em>Protoamaurolithus delicatus<\/em>. Best-preserved&nbsp;<em>Amaurolithus tricorniculatus<\/em>&nbsp;specimens are observed to show birefringence and the broken and poor-preserved use to be slightly or not birefringence.&nbsp;<em>Poralithus atlanticus<\/em>&nbsp;and&nbsp;<em>Amaurolithus tricorniculatus<\/em>&nbsp;appeared instantly in the geologic record, indicative of instantaneous speciation, resulting from horseshoe-structure duplication process.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"1020\" height=\"425\" src=\"https:\/\/blogs.ua.es\/messinianalicante\/files\/2025\/12\/figura04_cera.jpg\" alt=\"\" class=\"wp-image-471\" \/><\/figure>\n\n\n\n<p class=\"has-text-align-center wp-block-paragraph\">Figure. 3D recreation of <em>Poralithus atlanticus<\/em>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Cite as:\u00a0Lancis, C., Tent-Mancl\u00fas, J. E., Lancis, J., Est\u00e9vez, A. y Flores, J. A. (2025): Evolution of Neogene fossil ceratoliths (Coccolithophores) by duplication. <em>Marine Micropaleontology,<\/em><a href=\"https:\/\/www.sciencedirect.com\/journal\/marine-micropaleontology\/vol\/201\/suppl\/C\"> Volume 201<\/a>, 102530.<br><a href=\"https:\/\/doi.org\/10.1016\/j.marmicro.2025.102530\" target=\"_blank\" rel=\"noreferrer noopener\">https:\/\/doi.org\/10.1016\/j.marmicro.2025.102530<\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>The calcareous nannofossils of the genus&nbsp;Ceratolithus, known for their horseshoe shape (referred to as ceratolith), evolved from the&nbsp;Orthorhabdus rugosus, a rod-shape nannolith with three rodded blades (sinistral, median, and dextral). The sinistral and median blades gave rise to the sinistral &hellip; <a href=\"https:\/\/blogs.ua.es\/messinianalicante\/2025\/12\/01\/evolution-of-neogene-fossil-ceratoliths-coccolithophores-by-duplication\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":4347,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2392628],"tags":[2421057,2421056,2421061,2421062,2421059,2421058],"class_list":["post-468","post","type-post","status-publish","format-standard","hentry","category-nannofossils","tag-amaurolithus-tricorniculatus","tag-duplication","tag-early-pliocene","tag-nannofossils-evolution","tag-poralithus-atlanticus","tag-protoamaurolithus"],"_links":{"self":[{"href":"https:\/\/blogs.ua.es\/messinianalicante\/wp-json\/wp\/v2\/posts\/468","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.ua.es\/messinianalicante\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.ua.es\/messinianalicante\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.ua.es\/messinianalicante\/wp-json\/wp\/v2\/users\/4347"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.ua.es\/messinianalicante\/wp-json\/wp\/v2\/comments?post=468"}],"version-history":[{"count":3,"href":"https:\/\/blogs.ua.es\/messinianalicante\/wp-json\/wp\/v2\/posts\/468\/revisions"}],"predecessor-version":[{"id":472,"href":"https:\/\/blogs.ua.es\/messinianalicante\/wp-json\/wp\/v2\/posts\/468\/revisions\/472"}],"wp:attachment":[{"href":"https:\/\/blogs.ua.es\/messinianalicante\/wp-json\/wp\/v2\/media?parent=468"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.ua.es\/messinianalicante\/wp-json\/wp\/v2\/categories?post=468"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.ua.es\/messinianalicante\/wp-json\/wp\/v2\/tags?post=468"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}