Both Castilleja

Castilleja affinis vs Castilleja hispida

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, 7 times. We publish the rate, and then we tell you what actually separates them.

Confused 7x by our model Same genus Castilleja Method published

Side by sidefigs. a and b

Castilleja affinis, photographed by Ken-ichi Ueda
fig. a Ken-ichi Ueda, CC BY 4.0

Castilleja affinis

Coast Paintbrush
Castilleja hispida, photographed by John Krampl
fig. b John Krampl, CC BY 4.0

Castilleja hispida

harsh paintbrush

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Castilleja affinis Castilleja hispida 2 of 20 (10%)
Castilleja hispida Castilleja affinis 5 of 20 (25%)

The confusion is asymmetric, which is common and usually informative: it means one of these has a character the other lacks, rather than the two simply looking alike.

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

What actually separates themon the record

Family Both Orobanchaceae. The family does not separate them.
Genus Both Castilleja. Congeners, which is why this is hard.
Flowering Peaks in April versus May. If the plant is in flower, timing helps. (n = 1,639 and 979.)

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