Lysimachia rupestris F. H. Chen & C. M. Hu (Primulaceae): a new record for the flora of Vietnam and reconsideration of its taxonomical position

Lysimachia rupestris F. H. Chen & C. M. Hu is reported for the first time in Vietnam, in Cat Ba National Park. The supplemental description of its floral characters is applied. It has glabrous yellow corollas divided near to base, and stamens with short filaments connate basally into a ring and basifixed anthers opening by apical pores. The systematic position of L. rupestris F. H. Chen & C. M. Hu and its closely related species is also discussed.