Outer tepals emarginate or subcordate apically. 2n = 34, 36, 38, 40, 42, 44, 46.

Flowering May-Sep. Sandy to gravelly soils, mixed grassland communities, pine-oak wood-lands; 600-800 m; Calif.

Variety immemora is found on the eastern slope of the Diablo Range in southern San Benito County and in adjacent Monterey County. Hernandez spineflower is restricted to five small populations of a few individuals each. Plants of this taxon were variously identified as C. palmeri, C. biloba, or C. obovata prior to 1989. C. B. Hardham (1989) believed that the variety may be a product of past hybridization, given the variation in chromosome number. She also found meiotic chromosomes of three size classes, numerous nucleoli, and atypical pollen grains.