You can add all manner of links to the taxon page. Under the ABOUT tab you can add links to comments, journal posts etc. On the right is More Info, click on the Add Link button and away you go :-) If the link is pertinent to all child taxa, you can add the link to all of them in one go (there’s an option called Add to Children or something like that).
Examples:
Link to a key in a project journal post for the Amerila spp. adults - https://www.inaturalist.org/taxa/126085-Amerila
Link to a comment for notes on distinguishing brown Hippotion caterpillars - https://www.inaturalist.org/taxa/199458-Hippotion-celerio