Both Lithophragma

Lithophragma affine vs Lithophragma heterophyllum

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.

Confused 3x by our model Same genus Lithophragma Method published

Side by sidefigs. a and b

Lithophragma affine, photographed by Millie Basden
fig. a Millie Basden, CC BY 4.0

Lithophragma affine

San Francisco woodland-star
Lithophragma heterophyllum, photographed by Nicholas Wei
fig. b Nicholas Wei, CC BY-SA 4.0

Lithophragma heterophyllum

hillside woodland star

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Lithophragma heterophyllum Lithophragma affine 3 of 19 (16%)

Measured on 38,299 openly licensed, research-grade photographs. Full method and dataset.

What actually separates themon the record

Family Both Saxifragaceae. The family does not separate them.
Genus Both Lithophragma. Congeners, which is why this is hard.
Flowering Peaks in April versus April. Timing does not separate them. (n = 781 and 1,179.)

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.

Both recordsfull pages