It would have been a little better to have posted a full-body shot so the RBR(red body rings) can be shown for an accurate count, since that is a crucial meristical difference in the two. But from what I can see, it has a larger percentage of sinaloae in it, as opposed to nelsoni. Also, Sinaloan's can have a heavily mottled white snout as well. Does the first black ring have a break in it underneath the throat?, if it's complete, that's another trait more often seen in Sinaloae, rather than nelsoni.
I say this because of the thickness(or lack of thickness) of the black rings, and the angle that they taper, which looks to be very mild. This certainly isn't to say it doesn't, or can't have any nelsoni influence in it's genetic background, because MOST of the Sinaloans in the hobby today have influence from nelsoni to some degree, and vise versa, this is a fact. Extremely good examples of either one in the hobby are few and far between.
Anyway, from just what I can see in the photo, for all practical "hobby" purposes, ..it's a Sinaloan.
Below are two examples of good looking nelsoni, that CANNOT be mistaken for Sinaloan's.
best regards, ~Doug


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"Better to be silent and thought a fool, than to open mouth and remove any doubt!"