Acta Botanica 28. (1982)
1982 / 1-2. szám - BORHIDI ATTILA: Studies in Rondeletieae (Rubiaceae), III. The genera Rogiera and Arachnothryx
A. BORHIDI In consequence of these recognized correlations, it seems necessary to revalidate the genera Robiéra and Arachnothryx upon the following characterization: Rogiera Planch, in Fl. Serres 5: 442. 1849 Syn.: Rondeletia sect. Amoenae Standi. N. Amer. FI. 32: 49 (1918). Shrubs or small trees with usually large, foliaceous and reflexed stipules. Leaves opposite, usually large, pubescent or glabrous. Inflorescence broad, terminal, cymose-paniculate or cymose-corymbose, many flowered. Flowers 5-parted, calyx lobes small or large and foliaceous; corolla large, glabrous or antrorse-pilose outside, densely yellow-bearded in the throat, faucial ring, lamelles or denticles absent. Corolla tube puberulent or villous within, stamens included beneath the throat, filaments short, puberulent, anthers elliptic, included in the bearded throat. Style deeply bilobate, naked. Ovary globose, 2-loculate, disk annular naked. Placenta sphaeroidal, little, soft, with a punctiform central insertion to the septum. Ovules numerous, perpendicularly disposed to the placenta. Pollen grains sphaeroidal or subsphaeroidal, 3-colporate, exine thick, densely foveolate with tight irregular foveoles and exerted Fig. 1. Pollen of Rogiera ligustroides (Hemsl.) Borhidi. X1400 (Scanning-photo made by Dr. K. Vánky) Acta Bolanica Academiae Scientiarum Hungaricae 28, 1982