Diplacus "rutilus*
Santa Susana Pass Transition
A worth seeing transition zone has formed along the Santa Susana Pass. If you want to see them, go first to Stoney Point Park and look around. In the shadow of the stone blocks grows Diplacus rutilus (It starts flowering from the end of April).
May 2024. In this zone, Diplacus individual plants in transition or pure D. rutilus individuals may be found (cf. also the next map below).
Note: Pure D. rutilus plants are still mixed with plants in transition in this area.
More and more individuals appear with orange and dark red flowers if one has time to await their transition.
Diplacus rutilus grows mainly in the shade of large boulders in this summer dry landscape. It turns out that the branches of this plant shorten this way, that the bush takes on a spherical shape. The transition takes about ten to fifteen years. D. rutilus develops from Diplacus longiflorus plant individuals (color phase space). D. rutilus, in its cushion shape, originated around the year 2010.
https://academic.oup.com/evlett/article/7/5/293/7190212
The first phase model couples the phenotypes with the genotypes (color & R2R3Myb2 activity) here for Diplacus longiflorus and Diplacus rutilus with all intermediate stages. The model makes very reliable statements; see the truth table.
The TATA strings and the ear motif encode the gene activity of the MYB-TFs.
See: https://academic.oup.com/evlett/article/7/5/293/7190212 for genomic data.
Thanks to the authors for publishing the genomic data online. - We now know two ways of interpreting the Diplacus phenomenon. But we fear that only one interpretation will survive the test of time.
A massive distribution of yolk yellow flowered Diplacus longiflorus of the San Fernando Pass ecotype is pictured in the middle of the graph. In the West, east and Southeast of this distribution, dark red rutilus is localized. Note: Earlier Diplacus longiflorus flowers were all salmon yellow, and these yolk yellow forms might be precursors of the dark red rutilus forms.
