From central California, USA to Punta Rosarito, Baja California, Mexico. One record from British Columbia
UPPER: Bird Rock, La Jolla, California, USA. June 2000. Animal approx 11 mm long. LOWER: Egg mass. Punta Rosarito, Baja California, May 2001. Photos: Jeff Goddard.
Basically the external difference between B. strongi and B. californica is the texture of the notal surface - B. califonica being tuberculate, while B. strongi is smooth. Also, B. californica has a thin white line along the margin of the mantle, which is lacking in B. strongi. [see Dave Behren's message]. From photos on the Forum, another distinction would appear to be the shape of the egg mass, wide and flat in B. californica, cylindrical in B. strongi.
• Gosliner, T.M. & Bertsch, H. (1988). A review of the genus Berthella (Opisthobranchia: Notaspidea) from the Pacific Coast of North America. The Veliger, 31: 46-67.
Rudman, W.B., 2002 (March 18) Berthella strongi (MacFarland, 1966). [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/bertstro
Sponge prey of Berthella from the NE Pacific
From: Jeff Goddard, July 20, 2007
New photo of Berthella strongi
From: Ken Ashman, November 27, 2003
Berthella strongi from southern California
From: Jeff Goddard, April 10, 2002
Re: Berthella strongi
From: Dave Behrens, March 21, 2002
From: John Dorsey, March 20, 2002