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This beautiful small fern occurs in northern Mexico (Baja California Norte and Sur, and Sonora) and extreme southwestern US (Arizona and California). It is usually found in cracks in acidic rock cliffs and slopes, often in very dry exposed sites. I recognize two subspecies, based on Windham (1993a): N. californica ssp. californica (Yellow California Cloakfern) and N. californica ssp. leucophylla Windham (White California Cloakfern). These two taxa differ in the color of their farina (light to bright yellow, vs., bright white). This color difference is the result of significant differences in the chemical composition of the farina (Wollenweber, 1984).
The complete evolutionary history within N. californica, however, is complex. Notholaena californica ssp. californica is currently only known as an apogamous pentaploid (the sporophytes have five complete sets of chromosomes rather than the typical two sets, and produce unreduced spores, which develop into pentaploid gametophytes, which then produce a new sporophyte directly from their vegetative tissue, without sexual reproduction), based on a single chromosome count from a population in Arizona (Windham, 1993a). Notholaena californica ssp. leucophylla, on the other hand, has sexual diploid populations, apogamous triploid populations, and possibly tetraploid populations as well (Mickel and Smith, 2004). The relationship among these different populations (both within and between the subspecies) is in need of more study.