A New Combination and Change in Rank in Polycarpon (Caryophyllaceae), Endemic to California, U.S.A., and Mexico

Abstract

The name Polycarpon depressum Nutt. (Caryophyllaceae) is here investigated and lectotypified. According to a recent molecular investigation and based on the morphology and ecology of the taxon, the new combination and change in rank for P. tetraphyllum (L.) L. subsp. depressum (Nutt.) Iamonico are proposed for these plants endemic to California, U.S.A., and northern Mexico. A description of the subspecies is provided as is a comparison with the similar taxa P. tetraphyllum subsp. tetraphyllum, P.tetraphyllum subsp. alsinifolium (Biv.) Ball, and P. tetraphyllum subsp. diphyllum (Cav.) O. Bolòs & Font Quer.