A SURVEY OF ANTHER GLANDS IN THE MIMOSOID LEGUME TRIBES PARKIEAE AND MIMOSEAE

In a broad survey of anther glands in the mimosoid legume tribes Mimos eae and Parkieae, representatives from 30 genera with anther glands we re studied using scanning electron microscopy. Four kinds of anther gl ands could be distinguished. The Piptadenia-type gland, found in all b ut four of the genera surveyed, is usually spherical to ellipsoid in s hape and often borne on a stipe. The cells making up the gland vary in size among species and are often sculptured. Six different kinds of s culpturing can be recognized: smooth, reticulate, striate, rugulate, s cabrate, and papillate. The Gagnebina-type gland is the least speciali zed, consisting of a simple extension of the connective with irregular ly projecting cells. The Prosopis africana-type gland is borne ventral ly between the thecae, the connective extending hump-like over the ape x of the anther. The Pentaclethra-type gland, found only in the genus Pentaclethra, is distinguished by a median dorsal furrow and a ventral conical structure similar to a food body or osmophore. Anatomical sec tions revealed two different subtypes within the Piptadenia-type gland . Some glands are composed of a homogeneous matrix of isodiametric cel ls, whereas others have two layers: a peripheral layer of large radial ly elongated cells, and a central sphere of smaller isodiametric cells and large air spaces. Some characters of anther glands have clear tax onomic significance, and more detailed surveys within genera will undo ubtedly provide additional taxonomic markers.