Liu Bingcai, Wang Kai, Zong Ruiwen, Wang Yi, Xu Honghe
State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Nanjing 210008, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Plants (Basel). 2021 Nov 30;10(12):2631. doi: 10.3390/plants10122631.
Morphology and nomenclature are essential issues of botany, in which both extant and fossil plant taxa follow the same nomenclature code. Devonian (419.2-358.9 Ma) herbaceous lycopsid , one of the earliest coal-forming plants in geological history, possesses a characteristic, easily recognized, step-like stem and has been thought to be an index fossil for dating and correlating the Middle Devonian strata, especially those in the paleoblocks of Siberia, Kazakhstan, Xinjiang, and North China. Here, we systematically study the Devonian lycopsid in terms of its morphology and nomenclature, based on the new materials from the Middle Devonian Hujiersite Formation of West Junggar, Xinjiang, China, and the International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code). is determined as the type species of the genus, and a neotype is designated for that name. consists of fan- or rectangular-shaped leaves with awl-shaped or finger-like distal tips. Its leaves are pseudo-whorls and imbricately arranged on the stem surface forming distinct step-like structure.
形态学和命名法是植物学的重要问题，现存和化石植物类群都遵循相同的命名法规。泥盆纪（4.192 - 3.589亿年前）草本石松类植物是地质历史上最早的成煤植物之一，具有特征明显、易于识别的阶梯状茎，被认为是用于泥盆纪中期地层，特别是西伯利亚、哈萨克斯坦、新疆和华北古地块地层定年和对比的标准化石。在此，我们基于中国新疆西准噶尔中泥盆世胡吉尔斯特组的新材料以及《藻类、真菌和植物命名国际法规》（深圳法规），对泥盆纪石松类植物的形态学和命名法进行系统研究。确定为该属的模式种，并为该名称指定了新模式。由扇形或矩形叶片组成，远端叶尖呈锥状或指状。其叶片为假轮生，在茎表面呈覆瓦状排列，形成明显的阶梯状结构。
