种子蕨美羊齿类植物（callipterids）传统上被归入广泛使用的形态属美羊齿（Callipteris Brongniart 1849）。该属在北半球各地广泛分布，并且很久以来被认为是北半球陆相二叠系的标志化石，因此是晚古生代植物群中最为关注的一类植物。由于该类植物形态变异大，长期以来分类和命名十分混乱。上世纪80年代后期以后，通过对欧洲材料的深入研究，美羊齿类植物的分类学研究取得了突破性进展，诞生了国际学术界广为接受的新分类方案。由于美羊齿类是我国北方二叠纪最晚期植物群的主导类群，对这类植物的正确分类命名，影响到对我国二叠纪末植物群面貌的认识。当前项目将立足于新发现的具有表皮保存的化石材料，开展对我国美羊齿类植物的系统分类学研究，对以往已知属种进行厘定，力争把最新的分类方案运用于我国的美羊齿类植物，使我国美羊齿类植物的研究达到国际水平。

Callipterids as a group of seed fern, are traditionally included in the genus Callipteris Brongniart 1849. This group of plants are widespread on the northern hemisphere. Considerable importance was given to Callipteris Brongnirat among all late palaeozoic plant taxa. In Europe and North America the definition of the Carboniferous-Permian boundary in the continental deposits is traditionally based on the first occurence of Callipteris Brongniart. However, due to the high intraspecific variation of the foliage, Callipteris Brongniart includes about 135 species. Obviously a number of these species are rather doubt. The utilization of the Callipteris Brongniar has been extremely confusing. Subsequently, based on reinvestigation on the materials of Western and Central Europe in the 1980s, Callipterids have been reclassified (Kerp, 1988). The new classification system of Callipterids has been widely accepted. In China, callipterids are widely distributed in most late Permian terrestrial deposits, and even often are the dominant group in the flora. Therefore, a rational classification of the callipterids is critically necessary for a better understanding of late Permian floras. In this project, we focus on the taxonomy and nomenclature of the callipterids in the Permian terrestrial deposits all over China, using the new classification system. Cuticle anatomy will be particularly used for reevaluation of individual taxa. Our investigation will concentrate on the research of morphology, taxonomy, and palaeoecology of the species accommodated in various form-genera for callipterid foliage. Hopefully, this research will promote the systematic status of the Chinese callipterids to be academically on international level.