Hello...Police? I'd like to report a mimicry.
I was this many days old when I learnt that only one of these is a California sister.

I'd learnt to id the R one as a California sister in the Coastal range. Then seeing ones like L pic around Davis, I'd always called was the same thing. It was only when I accidentally loaded the L pic today into @inaturalist and saw multiple possible ids that I twigged.

The orange is a dot on California Sister (R pic) but it goes all the way to the wing edge of the Lorquin's Admiral (L pic). Plus the blue baring on the Cal. sister. But I'd never noticed this as they all usually go by me so quickly, & I'm not super observant (esp kid in tow).

I now have vague memories of looking carefully at the R pic & Art Shapiro's butterfly guide years ago (with my Dad when he visited, he's a keen butterfly guy) to work out that we'd seen a Cal. sister & my dad pointing out the diff. But had completely forgotten this till today.

Apparently, the palatable Lorquin's Admiral is potentially a Batesian mimic of the unpalatable California sister [ https://www.researchgate.net/publication/229447405_Evaluating_a_putative_mimetic_relationship_between_two_butterflies_Adelpha_bredowii_and_Limenitis_lorquini Prudic @eButterflyUSA et al].

And I fell for it hook, line, and sinker. Luckily I don't generally eat butterflies, but they had me fooled completely.

Still, a bit confused about the mimicry, as seems like the ranges/habitats are only partially overlapping.

Correct me on any details if I'm wrong (as just been googling around about this all). Also, I apologize that today pic (Left) isn't great. Our 4 y.o. asks me to take pics & then always sprints off laughing in the other direction, but I'm glad that he asked me as it's really cool.

Thanks, @WTF_R_species for this really nice thread with more details of the California Sister vs Lorquin's Admiral mimicry & less than perfect mimics! https://twitter.com/WTF_R_species/status/1250418804993282049