The Aptian is an age in the geologic timescale or a stage in the stratigraphic column. It is a subdivision of the Early or Lower Cretaceous epoch or series and encompasses the time from 125.0 ± 1.0 Ma to 113.0 ± 1.0 Ma (million years ago), approximately. The Aptian succeeds the Barremian and precedes the Albian, all part of the Lower/Early Cretaceous.
The Aptian partly overlaps the upper part of the regionally used (in Western Europe) stage Urgonian.
The Aptian was named after the small city of Apt in the Provence region of France, which is also known for its crystallized fruits. The original type locality is in the vicinity of Apt. The Aptian was introduced in scientific literature by French palaeontologist Alcide d'Orbigny in 1840.
The base of the Aptian stage is laid at magnetic anomaly M0r. A global reference profile for the base (a GSSP) had in 2009 not yet been appointed. The top of the Aptian (the base of the Albian) is at the first appearance of coccolithophore species Praediscosphaera columnata in the stratigraphic record.
In the Tethys domain, the Aptian contains eight ammonite biozones:
zone of Hypacanthoplites jacobizone of Nolaniceras nolanizone of Parahoplites melchioriszone of Epicheloniceras subnodosocostatumzone of Duffrenoyia furcatazone of Deshayesites deshayesizone of Deshayesites weissizone of Deshayesites oglanlensisSometimes the Aptian is subdivided in three substages or subages: Bedoulian (early or lower), Gargasian (middle) and Clansayesian (late or upper).
Antlers Formation, Cedar Mountain Formation, Cloverly Formation, Elrhaz Formation, Jiufotang Formation, Little Atherfield, Mazong Shan, Potomac Formation, Santana Formation, Twin Mountains Formation, Xinminbao Group, Yixian Formation
PictetiaEogaudrycerasGeorgiocerasLithancylusSalfeldiellaZuercherellaLowerEotetragonitesPseudosaynellaRolobocerasHelicancylusProchelonicerasProdeshayesitesShastocerasAmmonitocerasAustralicerasChelonicerasCicatritesColombicerasDufrenoyaMelchioritesParahoplitesUpperHypacanthoplitesSinzoviaTrochleicerasMathoceratitesMetahamitesNeosilesitesProtanisocerasAmmonoceratitesBeudanticerasGyalocerasHulenitesKnemicerasUhligellaAcanthohoplitesAcanthoplitesArgonauticerasBurckharditesCloiocerasDiadochocerasDiodochocerasEodouvilleicerasEpancylocerasEpichelonicerasGargasicerasJauberticerasKazanskyellaMathocerasMegatylocerasMiyakocerasNodosohoplitesNolanicerasProtacanthoplitesSomalitesTheganocerasTropaeumGabbiocerasTetragonitesDesmocerasHamitesVectibelusConoteuthisLowerTetrabelusPeratobelusParahibolitesHeminautilusCarinonautilusUpperZhuraleviaUpperEuphyllocerasUpperAdygeyaNaefiaBoluochia zhengiChaoyangia beishanensisConfuciusornis sanctusCuspirostrisornis houiJeholornis primaJixiangornis orientalisLargirostrornis sexdentorisLongchengornis sanyanensisLongipteryx chaoyangensisSapeornis chaoyangensisSinornis santensis/Cathayornis yandicaSonglingornis linghensisYanornis martiniYixianornis grabauiSarcosuchusHybodusJinanichthys longicephalusLycoptera davidiLycoptera muroiiPeipiaosteus paniProtosephurus liuiSinamia zdanskyiAnhangueraAraripedactylus dehmiAraripesaurus castilhoiArthurdactylus conandoyleiBoreopterus cuiaeBrasileodactylus araripensisCearadactylus atroxChaoyangopterus zhangiDsungaripterus weiiDsungaripterus brancaiEoazhdarcho liaoxiensisEopteranodon liiGegepterus changiHaopterus gracilisHongshanopterus lacustrisHuaxiapterus benxiensisHuaxiapterus corollatusHuaxiapterus jiiIstiodactylus latidensIstiodactylus sinensisJidapterus edentusLiaoningopterus guiLiaoxipterus brachyognathusLonchodectesLongchengpterus zhaoiLudodactylus sibbickiNemicolopterus crypticusNurhachius ignaciobritoiOrnithocheirus simusOrnithocheirus mesembrinusPricesaurus megalodonSantanadactylusSinopterus dongiSinopterus guiTapejara navigansTapejara wellnhoferiThalassodromeus sethiTropeognathus mesembrinusTropeognathus robustusTupandactylus imperator
