Taxonomic study of Pan-Himalayan Cyperus species which used to be placed in the segregate genus Pycreus

Abstract

This paper presents a taxonomic account of the Cyperus species which used to be placed in the segregate genus Pycreus (hereafter: Pycreus species) within the Pan-Himalaya, based on morphological and micromorphological studies. Twelve Pycreus species have been identified in the Pan-Himalaya region. Taxonomic keys, descriptions, type information, ecology, and distribution notes are provided for each species. The taxonomic significance of nutlet micromorphology is discussed, supported by high-quality digital images and scanning electron microscope (SEM) observations. Cyperus diaphanus var. gracilescens and Pycreus pseudolatespicatus are synonymized with C. diaphanus. A new combination is proposed for P. lijiangensis, and lectotypes are designated for C. angulatus, C. diaphanus, C. substramineus, C. sulcinux, C. delavayi and P. lijiangensis. Additionally, C. africanus is reported for the first time outside Africa.