This is one example of my research on biogeographic patterns of Boechera in California.Project description: The existence of a limestone hybrid Boechera sp. nov. in the San Bernardino Mountains, an apomictic, trigenomic triploid, has recently been discovered. Restricted to the higher elevation carbonate habitats in the San Bernardino Mountains, it occurs in very close sympatry with Boechera shockleyi, a USFS sensitive taxon and one of the three progenitors of the limestone hybrid, Boechera “grossii”. The other two parental genomes have been identified as not occurring in the San Bernardino Mountains, suggesting complex and intriguing biogeographic patterns.

Project goals: Investigate biogeography for the species, including taking a closer look at the connection between the Transverse Ranges of southern California and the Rocky Mountains to the northeast. Describe the species and characterize trichome morphology of the limestone hybrid Boechera “grossii” and all known progenitors.

The limestone hybrid, Boechera “grossii”, flowering and fruiting near the head of Furnace Canyon, San Bernardino Mountains.

A typical rosette of Boechera “grossii”, generally with less silvery-canescent basal leaves and slightly dentate margins of leaf blades.

Cauline leaves of Boechera “grossii”, lightly hairy with dentate margins and densely overlapping proximal leaves.

Boechera shockleyi, flowering and fruiting on the south slopes of Bertha Ridge in the rocky limestone outcrops, San Bernardino Mountains. Boechera shockleyi is one of three progenitors from which B. “grossii” is derived.

A group of rather typical rosettes of Boechera shockleyi, considerably more silvery-canescent than the limestone hybrid Boechera “grossii” and with strictly spatulate leaves.

Cauline leaves of Boechera shockleyi, densely silvery-canescent and lacking the dentate margins on densely overlapping cauline leaves.

notes:

Limestone hybrid Boechera “grossii” manuscript in prep., August 2013

Boechera “grossii” biogeography manuscript in prep., July 2013