Periodo Devónico
      Schizophoria S.striatula    (von Schlotheim 1813)

 Santa Lucia Formation. Cantabrian Mountain. Spain

    Schizophoria S.striatula   (von Schlotheim 1813)

 Santa Lucia Formation. Cantabrian Mountain. Spain

  Spinatrypa S.aspera  (Schlotheim, 1813)

 Holy Cross Mountains. Polonia.

Spinatrypa S.aspera  (Schlotheim, 1813)

 Holy Cross Mountains. Polonia.

   Spinatrypa S.dorsata   (Biernat, 1964)

 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  (Schlotheim, 1820)

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           (SOWERBY, 1818)

Smoke Creek.Moscow Formation. USA

Spirifer verneuili (Cyrtospirifer verneuili) (Murchison 1840)

 Belgica

    Strophodonta S.crassa    (Meek and Hayden, 1858)

Potter Granja Fm. de Alpena, Michigan.

Periodos