A systematic study of the red algal family Halymeniaceae

利用rbcL基因进行的分子系统发育分析表明：尽管迄今为止用于区分属的叶片质地和习性以及生殖结构的位置是同源的，但辅助细胞壶腹和叉形分支器具的形态在属水平上具有分类意义。分析还表明，这种同质性在种水平上具有重要的分类学意义，叶片的宽度和高度以及生殖细胞的大小等数量特征也具有同质性。(1)Carpopeltis affinis (Harvey) Okamura和C.prolifera (Hariot) Kawaguchi et Masuda和Sinkoraena由两个种组成，基于辅助细胞壶腹和carpogonial分支器具的相似性，应转移到Polyopes。rbcL基因序列支持这种转移（Sinkoraena属被还原为Polyopes的同义词）。(2)一个新种Polyopes tosaensis Kawaguchi et Masuda和一个恢复种Grateloupia subpectinata Holmes是已经包含在其他种中的隐种。(3)采集自冲绳县与那国岛的一种藻类，其特征是辅助细胞壶腹丝的细胞在二倍体化后立即分裂，大部分初级和次级丝的细胞同时分裂，形成葡萄状的球状小细胞簇。这种藻类被我们的rbcL解析为Halymeniaceae中五个单系分支之一，它被定位为Grateloupia分支的姐妹。在此藻类的基础上建立了Yonagunia新属（Y.tenuifolia Kawaguchi et Masuda, sp.nov.）。具有上述特征并属于同一分支的东南亚褐藻（Prionitis formosana (Okamura) Kawaguchi et Nguyen）被转移到Yonagunia。

Our molecular phylogenetic analyses using the rbcL gene indicate : the morphology of auxiliary cell ampullae and carpogonial branch apparatuses has taxonomic significance at the genus level in the Halymeniaceae, although the texture and habit of blades and the position of reproductive structures hitherto used for distinguishing genera are homoplacious. Our analyses also indicate that such homoplacious characters have taxonomic significance at the species level along with quantitative features such as the width and height of blades and the size of reproductive cells. (1)Carpopeltis affinis (Harvey) Okamura and C.prolifera (Hariot) Kawaguchi et Masuda and Sinkoraena consisting of two species should be transferred to Polyopes on the basis of the similarity of auxiliary cell ampullae and carpogonial branch apparatuses. The rbcL gene sequences support such transfers (The genus Sinkoraena was reduced to synonymy with Polyopes). (2)A new species Polyopes tosaensis Kawaguchi et Masuda and a reinstated species Grateloupia subpectinata Holmes are cryptic species that have been included in other species. (3)An alga collected from Yonaguni Island, Okinawa Prefecture, is characterized by the behavior of cells in the auxiliary cell ampullar filaments immediately after diploidization, most cells of the primary and secondary filaments simultaneously dividing to form grape-like clusters of small globular cells. This alga was resolved by our rbcL, analyses as one of five monophyletic clades within the Halymeniaceae, which is positioned as sister to the Grateloupia clade. A new genus Yonagunia was erected on the basis of this alga (Y.tenuifolia Kawaguchi et Masuda, sp.nov.). The Southeast Asian alga Prionitis formosana (Okamura) Kawaguchi et Nguyen that has the above-mentioned feature and included in the same clade was transferred to Yonagunia.