Invasion

Invasion Description

1st Record: Dillon Beach/CA/Tomales Bay-Pacific Ocean (1952, Osburn 1952, cited by Carlton 1979, as S. unicornis)

Geographic Extent

Dillon Beach/CA/Tomales Bay-Pacific Ocean (1952, Osburn 1952, cited by Carlton 1979, as S. unicornis); CA/Tomales Bay (1947, Carlton 1979; 2001, Fairey et al. 2002, as S. unicornis); Sacramento Landing/CA/Tomales Bay (2003, de Rivera et al. 2005)