Kalmar "chordamesoderm" tana nufin wani nau'i na musamman na sel waɗanda ke samuwa yayin haɓakawar amfrayo, wanda ke tsakiyar tsakiyar tayin mai tasowa. Yana haifar da notochord, tsari mai sassauƙa kamar sanda wanda ke ba da tallafi kuma yana taimakawa wajen kafa axis na amfrayo. Har ila yau, notochord yana da mahimmanci wajen haifar da haɓakar wasu sifofi, irin su bututun jijiyoyi, a lokacin haɓakar amfrayo na farko. An samo chordamesoderm daga mesoderm Layer na amfrayo mai tasowa.