Hauk Warren D, Parks Clifford R, Chase Mark W
University of North Carolina, Chapel Hill, NC 27516, USA.
Mol Phylogenet Evol. 2003 Jul;28(1):131-51. doi: 10.1016/s1055-7903(03)00032-0.
Ophioglossaceae are a putatively ancient lineage of ferns in which the aerial portion of the plant is composed of a single leaf. The simplicity of foliar morphology has limited the number of characters available for constructing classifications and contributed to taxonomic difficulties at nearly every level of classification within the family. Analysis of plastid DNA rbcL sequences from 36 species representing the diversity of Ophioglossaceae supported the monophyly of the family. Intrafamilial relationships were examined using rbcL and trnL-F plastid DNA sequences and morphological data. Individual and combined analyses of the three data sets revealed two main clades within the family, here termed ophioglossoid and botrychioid. In the botrychioid clade, Helminthostachys was sister to a broadly defined Botrychium, within which Botrychium in the narrow sense of some authors and Sceptridium were sister. Botrypus was paraphyletic, with Botrypus virginianus sister to Botrychium plus Sceptridium, and with Botrypus strictus sister to all other botrychioid species except Helminthostachys. In the ophioglossoid clade, Ophioglossum in the narrow sense was sister to Cheiroglossa plus Ophioderma, but relationships within Ophioglossum were not well supported.
瓶尔小草科是一个被认为古老的蕨类植物谱系，其中植物的地上部分由单叶组成。叶形态的简单性限制了用于构建分类的特征数量，并导致了该科几乎每个分类级别上的分类困难。对代表瓶尔小草科多样性的36个物种的质体DNA rbcL序列分析支持了该科的单系性。使用rbcL和trnL-F质体DNA序列以及形态学数据研究了科内关系。对这三个数据集的单独和联合分析揭示了该科内的两个主要分支，这里称为瓶尔小草类和阴地蕨类。在阴地蕨类分支中，七指蕨属是广义阴地蕨属的姐妹群，在广义阴地蕨属中，一些作者狭义的阴地蕨属和扇蕨属是姐妹群。阴地蕨属是并系的，维吉尼亚阴地蕨是阴地蕨属加扇蕨属的姐妹群，而狭叶阴地蕨是除七指蕨属外所有其他阴地蕨类物种的姐妹群。在瓶尔小草类分支中，狭义的瓶尔小草属是掌叶瓶尔小草属加蛇舌蕨属的姐妹群，但瓶尔小草属内的关系支持度不佳。
