Food-deceptive flowers primarily use visual signals (such as color) to mimic model plants and deceive insects into achieving pollination. Paphiopedilum micranthum is a food-deceptive orchid that has a pink labellum and two purple petals with a yellow base and has been proven to be pollinated by bumblebees. However, the chemical and molecular bases of the floral color are not well understood. We conducted targeted metabolite profiling and transcriptomic analysis to determine the color signal and its genetic basis in P. micranthum. We found that both anthocyanins and carotenoids contribute significantly to the formation of floral color that determines the color signal. Higher concentrations of anthocyanins (cyanidin and peonidin) and carotenoids (primarily lutein and zeaxanthin) were detected in the petal compared to the labellum. The upregulation of structural genes of CHS, F3′H, DFR and ANS on the anthocyanin biosynthesis pathway in petals was identified, as well as three genes of LCYE, BCH, and CCD4 on the carotenoid biosynthesis pathway. Furthermore, we discovered that three R2R3-MYBs and one bHLH transcription factors were co-expressed with the expression of different genes. These genes and transcription factors may be responsible for the spatial color difference of P. micranthum. Our study emphasizes that the color of this food-deceptive orchids is achieved through specific genes and transcription factors associated with the pigment biosynthesis pathway.

Flower color not only determines the quality and commercial value of ornamental plants, but it also plays a vital role in ecological processes such as pollinator attraction. This study aimed to investigate the relationship between flower color and the cellular physicochemical factors of Bletilla striata. The color space values of 21 samples were initially determined, followed by a selection of five samples with significant color differences for testing cell shape, total flavonoid content (ranging from 1.86 to 5.42 mg/g), total anthocyanin content (ranging from 0.52 to 292.62 (A530 − 0.25 ∗ A657)/g), cell pH (varying between 5.03 and 5.74), and metal ion content (including Al³⁺, Ca²⁺, Fe³⁺, K⁺, Mg²⁺, Na⁺, P⁵⁺, Zn²⁺, Mo⁶⁺, Cu²⁺, and Mn²⁺). The flowers of Bletilla were predominantly purple, pink, and yellow; and distributed in quadrants I, II, and IV on the a* and b* rectangular coordinate. The a* value was identified as the primary color indicator for this species. Total anthocyanin content and Zn²⁺ showed a significant positive correlation with a*, while Al³⁺, Ca²⁺, Fe³⁺, Mg²⁺, Na⁺, and Mn²⁺ demonstrated negative correlations. Cell shape, flavonoid content, and pH had nonsignificant correlations with a*. In conclusion, the total anthocyanin content and metal ions play crucial roles in determining the flower color of B. striata, which can have implications for pollinator attraction. Future research should focus on understanding the complex interactions between these factors to develop novel ornamental plant varieties with desirable flower colors and enhanced ecological functions.

A new orchid species, Liparis macrosepala, is illustrated and described from Yunnan Province, China, based on morphological and molecular analyses. This plant is characterised by the ovoid-fusiform, slightly compressed pseudobulbs with 4 or 5 leaves with slightly crisped margins on their apical half, dorsal sepal heart-shaped, lip with a bituberculate basal callus and a thickened folded lateral lobe on each side, centrally with one cavity with slightly raised margins, the column with a single pair of broadly triangular, obtuse wings. Maximum Likelihood and Bayesian Inference analyses of combined nrITS and plastid matK DNA sequences place this species in section Cestichis.

Calanthe graciliflora, an orchid species endemic to China, is one of the most widely distributed members of the genus Calanthe, occupying the highest latitudinal range and exhibiting strong cold tolerance. These traits suggest key adaptations to diverse and extreme environments, making it an ideal model for studying plant responses to climate variability. Ecological niche models (ENMs) are powerful tools for simulating species’ potential distributions across different time periods, thereby aiding biodiversity conservation. In this study, 75 filtered occurrence records of C. graciliflora and 19 climatic variables, derived from field surveys and herbarium records in China, were used to model the species’ potential distribution across 6 periods (Last Interglacial, Last Glacial Maximum, Middle Holocene, Current, Future 2050s, and Future 2070s). Research findings indicate that key environmental factors influencing its distribution include mean diurnal temperature range (bio2), mean temperature of the warmest quarter (bio10), annual precipitation (bio12), and precipitation of the driest month (bio14). Historically, suitable habitats for C. graciliflora were primarily concentrated south of the Qinling-Huaihe River region, closely associated with the Qinling, Luoxiao, Nanling, and Mount Wuyi ranges. During the Last Glacial Maximum, extensive suitable habitats existed in southwestern China, subsequently contracting to refugia in the Qinling and Mount Wuyi areas, underscoring these regions as refugia for C. graciliflora. Future projections indicate an overall decline in suitable habitat, highlighting the significant impacts of global warming on its long-term survival. Notably, this study represents the first application of the MaxEnt model to infer historical refugia of C. graciliflora while simultaneously integrating analyses of its future distribution shifts. This work fills the gap in long-term climate response research for this species and evaluates the impacts of climate change on its distribution, providing valuable insights for its phylogeography and conservation practice. By further identifying core habitats and clarifying their climate sensitivity, the findings provide a basis for developing targeted conservation strategies that prioritize key ecological areas and mitigate the risk of habitat loss.