These two are not on this page because a keyword tool suggested them. They are here because our own identification model genuinely mistook one for the other, on real photographs, 3 times. We publish the rate, and then we tell you what actually separates them.
| When the plant was | The model said | How often |
|---|---|---|
| Modiola caroliniana | Lysimachia arvensis | 3 of 20 (15%) |
Measured on 38,299 openly licensed, research-grade photographs. Full method and dataset.
| Family | Primulaceae versus Malvaceae. Different families, which is a real separation. |
|---|---|
| Genus | Lysimachia versus Modiola. |
| Flowering | Peaks in April versus April. Timing does not separate them. (n = 12,305 and 1,973.) |
What we do not have yet: the diagnostic morphological character that a botanist would key on, from a source we can cite. We are not going to invent one. Until we have it, this page tells you the two are genuinely confusable, how often, and what the taxonomy and the flowering data do and do not settle.