Fern leaves have surface coatings sealing them against dehydration. However, it is not clear whether wax compositions vary among fern species, and among ferns and seed plants.
Guo et al. analyse the wax mixtures of five fern species occurring in British Columbia by gas chromatography and mass spectrometry. Esters were the most abundant compounds in each species. Additionally, various fatty acid derivatives and polyketides were identified, many of them similar to those of seed plants like Arabidopsis thaliana. This result, together with other characteristics of the fern waxes, has significant implications on the evolutionary history of wax composition and biosynthesis.
Guo, Y., Li, J. J., Busta, L., & Jetter, R. (2018). Coverage and composition of cuticular waxes on the fronds of the temperate ferns Pteridium aquilinum, Cryptogramma crispa, Polypodium glycyrrhiza, Polystichum munitum and Gymnocarpium dryopteris. Annals of Botany, 122(4), 555–568. https://doi.org/10.1093/aob/mcy078