Studies On Taxonomy Of The Family Pottiaceae From Hebei Province

More than 1800 specimens of Pottiaceae of Hebei Province from two herbaria (HBNU, PE) have been examined. The author have studied the taxon of the family with the mathods of classical classification. The cladistic principles and methods have been employed in this study. According as the conception and taxonomic system of Zander (1993) about Pottiaceae, 5 subfamilies, 20 genera, 68 species and 8 varieties of the family are considered to be taxonomically recognizable entitles in Hebei Province. Description, figure and distribution are given to every species. Keys to the subfamilys, genera and species of this family in Hebei are provided. 1 species (Didymodon hedysariformis T. Otn.) is recorded new to China. 3 genera, Crossidium, Pterygoneurum and Hilpertia, and 10 species, Barbula ehrenbergii (Lor.) Fleisch., Barbula gracilenta Mitt., Hyophila setschwanica (Broth.) Hilp ex Chen, Syntrichia gemmascens (Chen) Zand., Hilpertia scotteri (Zand. & Steere) Zand., Tortula raucopapillosa (X. J. Li) Zand., Tortula atrovirens (Sm.) Lindb., Tortula leucostoma (R. Brown) Hook, et Grev., Pterygoneurum subsessile (Brid.) Jur. and Crossidium squamiferum (Viv.) Jur. are newly recorded to Hebei Province.The upper laminal cells of 72 species of Pottiaceae in Hebei province have been observed under light microscope (LM) and scanning electron microscope (SEM). The results show that there is highly comparability among species and genera of Pottiaceae at the shape, size and verrucosity of upper laminal cells. Under LM and SEM the verruga of cells shows some variation among the species and three types have been observed, i.e. (1) smooth or bulging ventrally and nearly flat dorsally, (2) round under LM, simple and half-balled under SEM and (3) lunular, dumbbell-shape or irregular shape under LM, bifid or multifid under SEM. Hyophila, Timmiella, Weisiopsis, Hilpertia and some species of Barbula have the type 1. The type 2 was found to coour in Anoectanigium, Didymodon, Gymnostomum, Hymenostylium, Molendoa and Pseudosymblepharis. The yrpe 3 occurring in Bryoerythrophyllum, Syntrichia, Tortella, Tortula, Trichostomum, Weissia and some species of Barbula.The capsules, peristome and spores of 28 species of Pottiaceae in Hebei province have been observed under LM and SEM. The results indicate that most spores are spheric or spheroidic, surface are covered with regularly or irregularly, small, verrucous, virgulate or pestle-like elements. Capsules are ovoid, ovoid-cylindric or cylindric, erect except for Timmiella anomala and Tortula mucronifolia with somewhat arcuate capsules. Peristome is haploperistomous, lancedate to linear, verrucous, sinistrorse except for Timmiella with peristome dextral weakly.With data obtained from the former research and personal observation, the cladistic principles and methods have been employed in this study. The morphological characters have been polarized for phylogenetic analysis. Cladograms have been gotten with five none-Pottiaceae genera: Polytrichum, Timmia, Ptychomitium, Encalypta and Grimmia as outgroup. As a result, a new system of the family Pottiaceae in Hebei province has been reconstructed.Based on the statistic and analysis of Pottiaceae, 3 dominant genera (over and including 8 species) consist of 34 species. This figure represents about 44.73% of the Pottiaceae flora from Hebei province.