Heads up: Some or all of the identifications affected by
this split may have been replaced with identifications of 
Diaulula. This
happens when we can't automatically assign an identification to one of the
output taxa.
Review identifications of Diaulula sandiegensis 47509
Diaulula. This
happens when we can't automatically assign an identification to one of the
output taxa.
Review identifications of Diaulula sandiegensis 47509
Taxonomic Split 19503
(Committed on 2017-02-26)
Split accepted by WoRMS: http://www.marinespecies.org/aphia.php?p=taxdetails&id=890436. The full text of the original paper is at https://www.researchgate.net/publication/308354922_Changing_spots_Pseudocryptic_speciation_in_the_North_Pacific_dorid_nudibranch_Diaulula_sandiegensis_Cooper_1863_Gastropoda_Heterobranchia
These two new concepts can be separated from photos. As the authors of the paper note,
the diagnostic trait separating the two morphs is not the shape of the spots, but rather the presence or absence of spots on the mantle margin: all of the ringed morphs (even those with solid spots) can be distinguished from the spotted morph by the absence of spots on the mantle margin
Here are some iNat photos that demonstrate the difference (click through for observations and photo credits):
D. odonoghuei
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D. sandiegensis (sensu stricto)
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Their ranges overlap, but not entirely:
D. odonoghuei is restricted to intertidal and bay habitats from Fort Bragg, California northwards, whereas D. sandiegensis is found throughout the entire region and is more common in subtidal habitats
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split into |
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How do we tell these two new species apart? I seem to remember you had something about that in an older change and now I can't find it.