<page_title> Aalenian </page_title> <table> <cell> Jurassic <col_header> System/ Period </col_header> </cell> <cell> Middle <col_header> System/ Period </col_header> </cell> <cell> Aalenian <col_header> System/ Period </col_header> </cell> <cell> 170.3 <col_header> Series/ Epoch </col_header> </cell> <cell> 174.1 <col_header> Stage/ Age </col_header> </cell> </table>
The Aalenian is a subdivision of the Middle Jurassic epoch/series that extends from 170.3 Ma to 174.1 Ma.