Mericarp and Seed Morphology of the genus Althaea L. (Malvaceae) in Turkey

Macro and micromorphological characteristics of mericarps and seeds of four species belonging to the genus Althaea L. (Malvaceae) distributed in Turkey are studied via a light microscope (LM) and a scanning electron microscope (SEM) in order to identify their these features and the importance of them as taxonomic evidence. The mericarps are light-dark brown or light yellow-brown in color and reniform or orbicular to reniform in shape. All the investigated species have white, stellate and pilose hairs only on the dorsal sides of mericarps except of A. cannabina and also epicuticular wax crystalloids on the lateral sides of mericarps. The surface pattern of the mericarps is reticulate-striate-ruminate at dorsal and scalariform-rugose at lateral faces. The seeds are dark brown, reniform, with rounded apex and base reniform, ranging from 1.76-2.76 mm in length to 1.38-1.95 mm in width, glabrous, strophiolate with hilum basal in position. Four types of seed surface ornamentation have been observed: rugulate-verrucate, striate, reticulate-striate and scalariform-rugose. A key using the mericarp and seed properties is provided to identify the studied species. The size and indumentum of mericarp, seed size and ornamentation have diagnostic values for discriminating the species of Althaea.y