The Geography of Phytochemical Races

2.7 North and Central America 99
population near San Luis Potosi (22°10′N, 101°W) was shown to accumulate ilicic
and costic acids (Higo et al., 1971) and have n = 36 (Payne, 1964).
2.7.9 Gaillardia pulchella (Asteraceae)
Gaillardia pulchella Foug. is a morphologically and cytologically diverse taxon that
enjoys a wide distributional range, from the southeastern United States westward
as far as Arizona (Fig. 2.62). Its chemistry has been the subject of numerous studies,
revealing the existence of several chemotypes. The coastal chemotype, ranging
from the southeastern seaboard through Florida to an area near Houston, Texas, is
characterized by a set of alkaloidal derivatives exemplifi ed by pulchellidine [206]
(see Fig. 2.63 for structures 206–209). The Rio Grande collection afforded the
ambrosanolide spathulin [207]. Collections from Live Oak County, Texas revealed
the guaianolide derivative gaillardin [208]. Plants collected in New Mexico and
Fig. 2.62 Map of sites for the Gaillardia pulchella study
Fig. 2.63 Compounds 206, an alkaloid, and 207–209, sesquiterpenes from Gaillardia pulchella.
Compounds 210 and 211, triterpenes from Dudleya