Phytologia (Sep 2006) 88(2) 208 PARAPHYMATOCEROS HASSEL, GEN. NOV. (ANTHOCEROTOPHYTA) Gabriela G. Hassel de Menendez Museo Argentino de Ciencias Naturales B. Rivadavia: Avda A. Gallardo 470, 1405 DJR, Buenos Aires, Argentina ABSTRACT Paraphymatoceros Hassel gen. nov. is described. It includes three species, P. diadematus Hassel sp. nov. from Chile, P. hallii (Austin) Hassel comb. nov. from USA and P. minimis (Mitt.) Hassel comb. nov. from South Africa. It differs from Phymatoceros Stotler, W. T. Doyle & Crand.-Stotl. in having a different kind of tuber, number of antheridia and spore wall ornamentation. KEYWORDS: Anthocerotophyta, Phymatoceros, Paraphymatoceros, Chile, USA, South Africa. Paraphymatoceros Hassel gen. nov. Thallus angustus, tenuis, tuberis scutiformibus marginalibus vel apicalibus viridulis vel auranticis. Capsula stomatophora cum columella. Sporae et pseudoelateres flavescentes vel nigrescentes, superficie distalis gibbosa, centrum areis triangularibus proximalibus baculis instructis. Differt a Phymatoceros tubera neque sphaerica neque pedunculata. Type species: Paraphymatoceros diadematus Hassel This genus is distinct from Phymatoceros Stotler, W. T. Doyle & Crand.-Stotl. by the antheridia which are more numerous per cavity, the tubers present under the notch of growing points at wide incipient lobes or at tips of narrow lobes, are scuteliform, nearly plane dorsally with a laminar border which continues from the thallus border, and bulging ventrally, covered with rhizoids. The sporophyte has a dehiscence line between two rows of yellow to orange coloured thick walled cells, seen in young capsules, as happens in Notothylas. The spores show on distal surface a number of rounded protuberances and
BioStor
