I have been having this issue as well. I’ve confirmed it happens across multiple taxa. After some additional playing around, my current theory is that it happens when there is no “visually similar” match in the selected taxa. For some reason instead of displaying “no results” it instead grabs the list of the most commonly observed taxa in the immediate area and ignores the filters.
Take this pelican, for example: (visually similar) + (taxon: pelicans) comes up with a couple of reasonable matches.
However, when I ask it to find a (visually similar) + (Taxon: bears) it obviously can’t find a bear that looks like this pelican so it spits out this:
The suggested species in the second case are all in the top “most observed” list for the county:
It may just be a case of the system pulling in the wrong list instead of showing a null result.
Have you noticed any searches using “visually similar” filter returning a “no suggestions” result? I thought I had, but going back to double check I only seem to be getting that result when I try it with extinct species: