Apparently, I have to navigate the Catalogue of Life ( which I do tend to find to be a bit confusing,) although it mentions at the website , it is as easy as one two three... Then try to find the plant & go back to start of adding a new entry, by providing the link.
Why not have a redirect, to the source automatic, instead of making it complicated & then the moderator having to confirm the link, that the person that is attempting to "add" the plant to this Database, to start with, already just visited ?
Seems that ought to make it much more simple & easier for those that don't know that would appear to be the source you use to "confirm" the very existence of the plant, before being able to add it? (To this Database.) May I please have some feedback on this matter ?

btw This very same issue had been asked of me, of just how to go about accomplishing this process. ( Result, was total failure - no newly added plant, with appropriate photo..)
I can barely manage it myself, let alone explain the entire process to someone else that has to translate the procedure of adding the link, to add a new plant., with photo.. ( End result- you lost addition of a new plant, to this Database !) Even though the Catalogue of Life has a translating function ! As otherwise, they may not be able to even read, or translate , to comprehend the instructions of exactly how to add it, & from where to obtain the link.
Meanwhile, I may sow seeds, of plants you haven't "confirmed" in your Database, but they are listed in mine...

You would be surprised how many good-intentioned people try to add plants that are already in the database or are taxonomically invalid, or have some issue with the name. The gatekeepers are actually really important for database hygiene. I myself have benefited from this moderation and learned new names for things as a result. I realize the delay can be frustrating but it's a human investment toward a clean database.

The response should be relatively quick (usually a day or less) and some explanation is usually given for a refusal, but you can always use Tree-mail to resolve questions or issues with the moderator, or start a thread in this forum if there is some issue which you feel deserves public discussion.

I think the goals of the moderators are efficiency and transparency. Given there are only so many hours in the day, they may not go on at length with an explanation, but I've always found that getting in touch about something will result in a response and a satisfactory resolution, even if I might disagree. What was the plant you wanted to add? Are you growing cacti from seed?

A newer cultivar. But no hurry at the moment. I haven't checked Mesa lately, after looking at the plant list, for all of a minute ( or less.) I wonder if they ever put seed list for cacti online. Otherwise, Phyto papers & small lot seeds permit would be about the only way to go these days & buy from Europe & pay even extra due to postage & bad exchange rate..

Just to add to what Baja has said, the Catalogue of Life is for species and nothospecies only. Hybrid cultivars will not be listed in the COL; instead, you need to provide a URL demonstrating the cultivar exists.

The preferred resource is the cultivar registry for that particular genus (for example, the RHS manages all Lilium and Orchid hybrid registrations, the links to which you can find in my forum signature), but you can use any link that shows the cultivar exists. Please note that if the URL used is not a cultivar registry or reputable nursery, though, it might take a bit longer for us admins/mods to verify the cultivar (we may also contact you with follow-up questions) and add it to the database.

I gave up on adding plants to the database, it is too complicated, and I can't figure it out.

Thank you Baja & Joshua, for some clarification. The info on other resources to use, was also very helpful.

For cultivars, most simply add a nursery link or two to show it's existence.

A tip for adding a new plant is to open an existing plant in the database and click the "Edit plant name" to see how it is entered. Some members think every blank line needs to be filled in and get stumped with trade names and series names but only the Genus, with species name if applicable, and cultivar, if it is one, needs to be added.

Thanks Sue, for that. As I like unusual seed cultivars...
Baja, I didn't order cacti seeds from Mesa, as that new website, isn't as easily to navigate, like before. Odd way of sorting. By expense, or popularity, but not by Genus, as far as I could tell... in search...Otherwise, by inquiry. Possibility of using a really old print catalog as reference for numbers, to try & order by might make it a bit more easy, to ask about !