Equicalastrobus chinleana

Strobilus either reproductive structure of a horsetail, composed of numerous scales, which open to release the spores when they mature.

Horsetails are primitive plants that appeared during the late Devonian, they reproduce by spores, like bryophytes (mosses, liverworts...) but less evolved than spermatophytes (gymnosperms, angiosperms) that reproduce by seeds.

Horsetails have a rhizome or horizontal underground stem from which roots and two types of aerial stems arise: fertile, which end in a strobile and appear first in spring, and sterile, green in color with whorled branches and in which an articulated structure can be differentiated due to the presence of nodes and internodes. Microphylls or reduced leaves appear around the nodes of the stems. Due to these long shapes, the horsetail plants They are commonly known as horsetail.