硅藻中国一新记录种——泉生平片藻

利用光学显微镜和扫描电子显微镜对采自湖南省绥宁县巫水水域的硅藻标本进行了观察研究，鉴定出其中一种为硅藻中国新记录种——泉生平片藻［Tabularia fonticola (Hustedt) C.E. Wetzel & D.M. Williams］，该种具有以下鉴别特征：(1) 壳面轮廓为线形披针形，中央胸骨宽，线纹短且宽。(2) 横主肋和纵细肋硅质化增厚。(3) 孔纹开口被数条横向硅质条组成的筛板所遮拦。(4) 每个壳面仅在其一端着生一个唇形突。(5) 壳套顶孔区孔纹有序排列。(6) 第一环带开放。该研究首次报道了泉生平片藻的前正常营养期细胞的超微结构特征，研究结果不仅增加了对泉生平片藻的超微结构认识，而且扩展了其地理分布区域。

Tabularia fonticola (Hustedt) C.E. Wetzel & D.M. Williams, a Newly Reported Diatom from China

This study identifies one diatom species as Tabularia fonticola (Hustedt) C.E. Wetzel & D.M. Williams after examining the specimens collected from the Wu River, which runs through the Suining County of Hunan Province, by using light and scanning electron microscopy. The observation results demonstrate that the identified T. fonticola has the following diagnostic characters: (1) linear lanceolate valve outline with wide sternum and shortened and wide striae. (2) Thickened silica virgae and vimines. (3) Areola occluded by cribrum composed of a few transapical silica bars. (4) Only one rimoportula produced at an apex for each valve. (5) Ocellulimbus with regularly arranged porelli. (6) Open valvocopula. This article reports the ultrastructure characters of the pre normal frustule of T. fonticola for the first time. The study results not only improve the understanding of the ultrastructure of T. fonticola, but also add a new geographical distribution region for it.