Amphicarpy in the Cyperaceae, With Novel Variation in the Wetland Sedge Eleocharis caespitosissima Baker

Abstract

Amphicarpy, the heterocarpic production of serial and basal fruits, occurs in the Cyperaceae in species of the primarily mesophytic genera Bulbostylis and Trianoptiles and in species of the helophytic genera Eleocharis and Schoenoplectus. There is a variety of breeding systems and growth forms across these amphicarpic species. Eleocharis caespitosissima is amphicarpic, with basal fruits buried by positively geotropic culms. The seeds of basal fruits in this species may arise asexually. The selective pressures likely to be important in the development of amphicarpy in the Cyperaceae are discussed.