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Leaf Anatomy of Fourteen Species in Carex Subgenus Indocarex (Cyperaceae)


Among the subgenera of the genus Carex, the subgenus Indocarex has been sel-
dom studied in any respects, Its systematic position and its subdivision are still disputable.
Leaf anatomy of 14 species in the subgenus lndocarex from China was studied. The anatom-
ical characters are proved to be systematically valuable. (1) Characters of lamina transverse
section: All leaves of these 14 species are dorsiventral. The outline mostly V-shaped, occa-
sionally flat or nearly flat, with adaxial lateral rib in each half of lamina and some of them
flanged. The cells of adaxial surface larger than those of abaxial surface, and the epidermal
cells over veins usually smaller than others. Air-cavities between vascular bundles are well de-
veloped, and bulliform cells also well developed in most taxa. The vascular bundles are collat-
erai, bundle sheaths double-layered, and the outer sheath parenchymatous and the inner
sheath fibrous. (2) Characters of lamina epidermis: The shape of the cell on both surfaces is
generally rectangular, and the anticlinal wall of epidermal cell sinuous; stomata is paracytic,
elliptic to oblong, rarely sub-circular; prickles occur on adaxial surfaces of certain species;
papillae are only obvious on abaxial surface of C. moupinensis Franch. The characters of
transverse section and epidermis of leaf blades of these 14 species differ from each other to
certain degree, and closely related species are similar in anatomical characters. The anatomi-
cal characters of lamina are of value for classification at specific and sectional level of the sub-
genus Indocarex. Despite of the variation of these characters among species, a certain num-
ber of characters appears to be shared by the members of the subgenus, and some of the com-
mon characters are primitive. In addition, some gross morphological characters are common
and primitive also.  Therefore,  the subgenus Indocarex may be primitive in the genus
Carex. The anatomical and morphological characters of C. scaposa C. B. Clakre and C.
densifimbriata Tang et Wang ex S. Y. Liang are distinct. The two species and their allies
should be treated as section instead of subsection.  The three species in the section
Polystachyae share some anatomical characters and comprise a coherent group.


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