Castilleja (Paintbrush) Species of Texas
Castilleja, a member of the parasitic family Orobanchaceae, includes over 200 species, seven of which are native to Texas. A few of these seven species include several subspecies, most notably C. purpurea, which has a number of subspecies that vary greatly in color.
The colorful components of Castilleja are actually specialized bracts rather than actual petals, and surround small, modestly colored flowers.
Castilleja are hemiparasites that do photosynthesize, but also draw water and nutrients from host plants by penetrating the roots of those plants with specialized roots called haustoria. Because of this, Castilleja does not thrive in isolation. Depending on the composition of a botanical community, Castilleja can increase or decrease biodiversity by either parasitizing on more dominant or secondary plants.
Castilleja is often found thriving among stands of lupines, as lupines are nitrogen-fixing and produce a number of toxins that may inhibit herbivory. Castilleja draws these chemicals and nutrients from lupines and does well as a result.
Species of Castilleja native to Texas, and notes on their distribution in the state:
C. indivisa (Texas Paintbrush) (Eastern half of state, mostly excluding Cross Timbers ecoregion)
C. integra (Wholeleaf Indian Paintbrush, Squawfeather) (Mostly West Texas)
C. integra var. integra
C. lanata (Sierra woolly Indian paintbrush) (mostly West Texas)
C. mexicana (Mexican Indian Paintbrush) (Big Bend region)
C. purpurea (Prairie Paintbrush) (Edwards Plateau and north into the Cross Timbers ecoregion)
C. purpurea var. citrina (Lemon Paintbrush) (Central Great Plains, Edwards Plateau. Occurrences reported near San Saba/Mason/Sonora)
C. purpurea var. lindheimeri (Lindheimer's paintbrush) (Uncommon, along Balcones Fault Zone)
C. purpurea var. purpurea (Purple Paintbrush) (Primarily found in Cross Timbers ecoregion, with some occurrences south to Llano Uplift)
C. rigida (Rigid Paintbrush) (Uncommon, mostly western Edwards Plateau and Trans-Pecos)
C. sessiliflora (Downy Painted Cup) (West Texas and panhandle)
See sources:
https://oleaeuropea.wordpress.com/2011/07/27/indian-paintbrush-a-pretty-parasite/
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