Structure and Symmetry of Species of the Asplundia Group (Cyclanthaceae) Having Monopodial Vegetative Axes: Schultesiophytum chorianthum, Dicranopygium Sp. Nov., Asplundia rigida, and Thoracocarpus bissectus

Abstract

Individual vegetative axes of Schultesiophytum chorianthum, Dicranopygium sp. nov., Asplundia rigida, and Thoracocarpus bissectus have monopodial growth. Each adult leaf subtends a first-order lateral bud, that is, either a vegetative bud, inflorescence bud, or bud of uncertain nature (T. bissectus). Both first-order vegetative and inflorescence buds are borne intermittently on the vegetative axis; in addition, each sort of first-order bud may occur separately between two consecutively formed buds of the other type or in a group of two or more successively formed individuals. The prophyll of each first-order vegetative or inflorescence bud is a bicarinate scale leaf and is inserted above a very short hypodium. Also, on first-order vegetative buds juvenile leaves always develop immediately distal to the prophyll. Thoracocar pus bissectus differs from the other three species in forming supernumerary buds which occur sporadically in either of two positions on basal portions of first-order lateral buds. In ea...