The Ascidians Styela barnharti, S. plicata, S. clava, and S. montereyensis in Californian Waters

Reexamination of the holotype of Styela barnharti Ritter and Forsyth, 1917, shows that it is Styela plicata (Lesueur. 1823). The species designated Styela barnharti by Van Name (1945) and subsequent authors is Styela clava Herdman. 1881, an asiatic form probably introduced into Californian waters in the late 1920\u27s. The latter species is distinct from the native west coast form Styela montereyensis (Dall. 1872)