Typical: Ceratozamia euryphyllidia, the largest type?

By Matthew C. Pace

Oct 11 2019

Plant specimens come in all shapes and sizes, but they are usually confined to a single sheet, rarely two sheets. To capture the full size of the endangered cycad Ceratozamia euryphyllidia, including an entire 10.5 ft long leaf, this amazing type specimen covers an astounding nine sheets and one bulky cone!

This might hold the record for the largest plant type specimen!

Cycad leaves are compound, meaning the leaf is composed of several smaller segments called leaflets, which in turn are attached to a central rachis; this whole structure is a single leaf. An analogy is leaflets are to a leaf as teeth are to a comb. One way to distinguish a single compound leaf vs a branch with many leaves is to look for a bud: buds form at the base of leaves, so compound leaves lack buds at the base of each leaflet, whereas branches will have a bud at the base of each leaf. Scan through the specimens to 'walk along' this very big leaf.

Cycads are an ancient lineage of seed-bearing plants that were very species-rich during the age of dinosaurs. Although cycads superficially resemble palms, they bear cones and are more closely related to pines and the gingko tree.

Stevenson, D.W., S. Sabato, M. Vázquez Torres. 1986. A new species of Ceratozamia (Zamiaceae) from Veracruz, Mexico with comments on species relationships, habitats, and vegetative morphology in Ceratozamia. Brittonia, 38: 17-26.