Periodo Devónico
Schizophoria S.striatula

 Santa Lucia Formation. Cantabrian Mountain. Spain

Schizophoria S.striatula

 Santa Lucia Formation. Cantabrian Mountain. Spain

Spinatrypa S.aspera

 Holy Cross Mountains. Polonia.

Spinatrypa S.aspera

 Holy Cross Mountains. Polonia.

Spinatrypa S.dorsata

 Portilla Formation. Cantabrian Mountains. Spain.

Spinatrypina sp

 Santa Lucia Formation. Valle del Esla . Leon. Spain.

Spinatrypina sp 

Santa Lucia Formation. Cantabrian Mountains. Spain.

Spinocyrtia S.ostiolata

Gerolstein. Germany.

Spinocyrtina S.elegans

Colle ( Leon ).

Spinocyrtina S.elegans

Colle ( Leon ).

Spinocyrtina S.elegans

Colle ( Leon ).

Spinocyrtina S.elegans.

Colle ( Leon ).

Spirifer S.P

Smoke Creek.Moscow Formation. USA

Spirifer verneuili (Cyrtospirifer verneuili)

 Belgica

Strophodonta S.crassa

Potter Granja Fm. de Alpena, Michigan.

Periodos