This is widespread in southastern states, and perhaps less concentrated on dry calcareous sites than typical spithamea. C. catesbeiana differs (W) in its more twining stems in the upper part, mostly 8-14 dm high (versus up to 6 dm), its leaves overtopping the stem apex by < 1 cm (versus 1.5-6 cm), and peduncles ca. 5-10 cm long (versus 3-5 cm). Typical plants tend to be more pubescent. Distinction remains uncertain, and mapping here is provisional.