Variation Patterns and Systematics of the Widespread Species Epilobium angustifolium L.(Onagraceae) in China
柳兰广布种在中国的变异式样及其分类学

Cytological, morphological, and geographical studies of Epilobium angustifolium in China reveal two partly distinct, partly overlapping entities that are best treated as subspe- cies. The diploid (n=18) subsp. angustifolium has smaller, triporate pollen grains, typically glabrous stems and leaves, and smaller leaves and flowers, and occurs in colder, more northern areas, and at higher elevations in overlap zones. The tetraploid (n=36) subsp. circumva- gum has larger pollen with a mixture of quadriporate pollen grains, pubescent stems and leaves, and larger leaves and flowers, and occurs in warmer parts of southern China and at lower elevations. We report 11 chromosome counts, six diploid and five tetraploid, includingthe first reported tetraploids in Asia.