Scanning electron micrographs of leaves of British Carex species, 2. Subgenus Vignea. Carices with several hermaphrodite spikes

Abstract

Abstract Most species of Carex subgenus Vignea have several similar hermaphrodite spikes, channelled or keeled leaves, smooth below and smooth to roughened above with low papillae at the apices of the epidermal cells, and are hypostomous with superficial stomata. Most of the variation is quantitative, in growth-habit, in the breadth and folding of the leaf, in the roughness of the upper leaf surface, and in the form and degree of the toothing of the margins and keel of the leaf. The main exceptions to this pattern are the section Heleoglochin, where the stomata are in distinctive pits or grooves in the lower surface, the section Physoglochin (C. dioica and related species), which is dioecious (in Europe), single-spiked and has linear leaves, and the section Heleonastes (C. lachenalii) which has characteristically papillose leaf surfaces and the similar C. canescens (section Canescentes) which is amphistomous. The approximate size and distribution of stomata, papillae and teeth (‘prickles’) of the species are listed. The overall pattern of variation is such that consistent differences at sectional level are few.