The lead for these two photos still says 'copepod'; they are larval mites, which have only 6 legs at first, so the re-classification as Arachnida, Acari is correct. The ID banner needs updating. 06.06.2022.

...a crustacean larva to me. What characteristics make this a mite and not a crustacean?

I apologize for not doing my due diligence! I agree this is the nauplius larval stage of a copepod, but I'm way out of my field. Check https://en.wikipedia.org/wiki/Crustacean_larva#/media/File:Nauplius_larva_of_a_cyclops_copepod.jpg. Larval mites appear grossly similar, with 6 legs, but not quite. Thanks for giving me a shove! The post still needs updating; it's confusing as is.

I agree that the post could be confusing, but titles are chosen by the contributor and BugGuide editors generally won't change them unless they are offensive in some way.

As it happens, "wrong" titles can actually be helpful. Someone else coming to the site might think they have a photo of a water mite. If they do a search, this image could turn up in the results and lead them to the correct ID.

Yes, intentional placement in 'homoplastic sites' can indeed be helpful, expanding the knowledge base of the viewer and realigning their search; however, two prominent IDs that are as different as Arachnid and Crustacean are confusing because they are not clarified -- in this case the main ID banner is the one incorrect. This could be alleviated simply by adding a 'Correction' (not necessarily labeled as such) saying something like [Identification updated, Copepod Custacean, by ___(updater name)____.] added under the op lead or photos. That would remove any confusion. Over the years I have noticed several examples of this, many quite useful to me, others too far out to be very useful, and some, just confusing -- but easily clarified by the person making the page assignment.