Spore Output And Cell Surface Structure Of Selected Liverworts, And Species Diversity Of Drepanolejeunea In China

Liverworts, the second largest group of bryophytes, contain about5000-8000species in the world. The knowledge of liverworts, however, is still much poorer than that of the other higher plants. The present paper deals with the spore output and surface structure of liverworts as well as species diversity of Drepanolejeunea in China. The main results are as follows:(1) The spore output of84selected species belonging to26families was investigated by the direct artificial counting method or hemacytometer counts. Among them, a total of82species are reported for the first time. The mean spore output per capsule ranges from181in Cyathodium foetidissimum to465000in Calypogeia tosana. The taxa, such as Ricciaceae and Cyathodiaceae mainly in water or caves, have lowest spore output in Marchantiopsida, ranging from181to300. The Lejeuneaceae predominantly on living leaves has lowest and stablest spore output which ranges from257in Cololejeunea magnilobula to5038in Ptychanthus striatus.(2) The presence of surface waxes in Oryzolejeunea, Stenolejeunea (Lejeuneaceae), Telaranea (Lepidoziaceae), and Metacalypogeia (Calypogeiaceae) are confirmed for the first time by a light microscope and scanning electron microscope study after washing the shoots in chloroform. The surface projections of liverworts are divided into11types, two of them, plate-like/membraneous type and rodlet-like type are usually of a wax origin. Both cell wall papillae and surface wax are stable, and of great taxonomic significance in liverworts.(3) A taxonomic study on Chinese Drepanolejeunea reveals that20species are present in China. Drepanolejeunea obtusifolia T.Yamag., an endangered liverwort in Japan, is newly found in China. The Indian Drepanolejeunea longifolia Ajit P.Singh, V.Nath et A.K.Asthana described recently by the Indian bryologists is proposed as a new synonym of Drepanolejeunea angustifolia (Mitt.) Grolle.