China. Strophomena amoena Strophomena billingsi Strophomena concordensis Strophomena costellata Strophomena dignata Strophomena extensa Strophomena euglypha...

Dendrograptus sp. ?Airograptus betieri Strophomenata Actinomena orta ?Strophomena barbieri Fezouata Formation Ordovician radiation Zaouïa Schists at Mindat...

†Stigmatella †Strophomena †Strophomena alpenensis †Strophomena costata †Strophomena crassa †Strophomena elongata †Strophomena erratica †Strophomena extenuata...

littletonensis †Strophomena †Strophomena abnormalis †Strophomena biplacata †Strophomena cedarensis †Strophomena cicatricosa †Strophomena costata †Strophomena dorsata...

demissa †Strophomena †Strophomena alpenensis †Strophomena costata †Strophomena crassa †Strophomena elongata †Strophomena erratica †Strophomena extenuata...

†Stigmatella †Strophomena †Strophomena concordensis †Strophomena erratica †Strophomena extenuata †Strophomena neglecta †Strophomena nutans †Strophomena planumbona...

†Stigmatella †Strophomena †Strophomena concordensis †Strophomena erratica †Strophomena extenuata †Strophomena neglecta †Strophomena nutans †Strophomena planumbona...

†Stigmatella †Strophomena †Strophomena concordensis †Strophomena costellata – or unidentified comparable form †Strophomena neglecta †Strophomena planumbona...

Strophomena filitexta, a strophomenide from the Ordovician of Minnesota. Ventral valve seen from the inside, illustrating strongly-developed dental plates...

†Stigmatella †Strepsodiscus †Strophomena †Strophomena billingsi †Strophomena filitexta †Strophomena incurvata †Strophomena plattinensis – or unidentified...