110 
PROCEEDINGS OF THE CALIFORNIA ACADEMY OF SCIENCES 
Series 4, Volume 65, 28 Sept. 2018, No. 3 
2015 through 2017 and are listed systematically in Section 1 below. For each of these we include 
their known southern range limit and previous northern range limit, along with the primary refer¬ 
ences documenting those. We also include, as “additional northern localities,” records from sites 
located between the new and previous northernmost localities; for a few species these also include 
older, previously undocumented or obscure records. 
New northernmost sites were spread over 26 degrees of latitude, from La Paz, Baja California 
Sur (for Carminodoris bramale ) to Port Hardy, Vancouver Island, British Columbia (for Triopha 
maculata ). Range extensions varied in length from 23 to 700 km, with a mean of 270 km (SD = 
201 km, n = 23). 
Section 2 covers species found at or near previously determined northern range limits. 
Each of the recent collecting localities mentioned below is listed with its geographic coordi¬ 
nates in Table 1. 
I. New northernmost locality records 
Heterobranchia 
Pleurobranchida 
Berthella strongi (MacFarland, 1966). MacKerricker State Park, Mendocino Co., California, 
1 specimen, low rocky intertidal, 4 July 2016 (Pirrone 2016) to El Tomatal, Baja California, 
Mexico (Goddard and Green 2013; for image see <https://www.inaturalist.org/ 
observations/2957040>). 
Previous northernmost locality: Moss Beach, California (Bertsch et al. 1972 [as Pleuro- 
branchus strongi]). 
Additional northern localities: Salt Point State Park, Sonoma Co., California, 1 specimen, low 
intertidal, 9 May 2016 (observed by WP, DM, PD); Drake’s Estero, Point Reyes National Park, 
Marin Co., California, 1 specimen, with an egg mass, next to its sponge prey Oscarella carmela, 
under a low intertidal cobble, 8 June 2016 (observed by JG). 
Remarks: Behrens (1998, 2004) reported B. strongi found by Mike Miller off of Nanaimo, 
British Columbia. No collection information, including date, or image were given, but M. Miller 
(personal communication to JG, 9 July 2016) dove there in 1998, and the record therefore may rep¬ 
resent an ephemeral range extension driven by the strong 1997-98 El Nino event. However, it 
should be noted that this species has not been reported from north of California before or since, and 
without an image or specific collection data we consider this record unverified. 
Nudibranchia 
Goniodorididae 
Okenia angelensis Lance, 1966. Miwok Beach, Sonoma Co., California, 1 specimen, 5 mm 
long, low rocky intertidal, 27 May 2017, observed by Colby Davidson (Fig. 1A) (Hollis Bewley, 
personal communication to JS, 5 June 2017) to Punta Rosarito, Baja California, Mexico (Goddard 
and Hermosillo 2008); Bahia de los Angeles, Baja California (Lance 1966) and Chile (Munoz et 
al. 1996; Schrodl 1996). 
Previous northernmost locality: San Francisco Bay, California (Lance 1966). 
Remarks: The new record is also significant for its location on the outer coast, outside the sea¬ 
sonal warm water refiigium of San Francisco Bay. 
