This study reports on extensive and in-depth investigations into the morphological, photosynthetic, and physiological indices of 10 different types of Cypripedium plant introduced from Changbai Mountain. It is an important prerequisite for the ex situ conservation of Cypripedium plants to provide new insights into their photosynthesis. This result can not only promote the production of vegetative plants but also promote the production of plants with lots of flowers and the physiological characteristics of Cypripedium plants for promoting the artificial introduction and cultivation of wild resources. A critical comparison of the results showed that high light intensity is one of the causes of the reduction in photosynthesis in the samples. Cypripedium macranthum had the most morphological advantages, while Cypripedium guttatum, the smallest plant type, had the lowest plant morphogenesis. Photoinhibition began daily at 12:00 pm and reached a second peak at 14:00 pm in all 10 types. C. macranthum, Cypripedium ventricosum, and Cypripedium calceolus had greater photosynthetic capacity than the other types. Using principal component analysis, the order of photosynthetic physiological characteristics of the 10 Cypripedium plants was CCMY > CVPP > CCRY > CMPP > CVRR > CSPY > CMWW > CMLL > CMDD > CGWW. These results lay the groundwork for future research on Cypripedium resource distribution and artificial conservation.

A Cypripedium plant was discovered in Wangqing County, Changbai Mountain, Jilin Province. This newly discovered plant of Cypripedium not only inhabits the same natural habitat as Cypripedium calceolus L. and Cypripedium × ventricosum Sw. but also has a morphology intermediate between that of C. calceolus and C. × ventricosum. Its dorsal sepals, petals, and synsepal are similar to those of C. calceolus, while the color of its lip is intermediate between that of C. calceolus and C. × ventricosum. For the purpose of distinguishing the newly discovered plant of Cypripedium from other Cypripedium plants, we provisionally named it W1. To further verify the taxonomic status of W1, we introduced three identified forms of C. × ventricosum and conducted molecular biology analyses with W1, C. calceolus, and C. × ventricosum. The analyses further confirmed the relationship between W1 and C. × ventricosum, and the phylogenetic analysis of the nuclear region demonstrated a close relationship between W1 and C. calceolus. Collectively, the morphological and molecular evidence indicates that W1 is a product of the backcross between C. × ventricosum and C. calceolus. Although it shows morphological differences from typical C. × ventricosum, it can still be considered a form of C. × ventricosum. We further investigated the chloroplast genome of this form of C. × ventricosum and determined that its total genome length was 196,850 bp. The genome contains 132 genes, including 87 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. By analyzing the phylogenetic position and chloroplast genome of the form of C. × ventricosum, this study clarified the relationships among Cypripedium taxa with similar morphological characteristics, laying a foundation for research on orchid evolution and species conservation.