Gnetum

Gnetum is a genus within the gnetophytes, a group of gymnosperms (cone-bearing plants) that, intriguingly, share closer evolutionary ties to angiosperms (flowering plants) than to other gymnosperms. While gnetophytes include 65 known species, Gnetum is the largest genus, consisting of 34 species (Britannica). Unlike the other two genera of gnetophytes, Welwitschia and Ephedra, which thrive in arid environments, Gnetum flourishes in tropical climates and more closely resembles flowering plants in both structure and function.

In the Amazon, seven species of Gnetum can be found (Kew Royal Botanic Gardens). These plants vary in form, taking on the appearance of shrubs, vines, and small trees (Acevedo-Rodríguez, 2020). Like cycads, Gnetum species are insect-pollinated gymnosperms (Gong, 2015), adding to their unique status as a bridge between the gymnosperms and angiosperms. This evolutionary significance provides a fascinating glimpse into Earth's natural history, offering valuable insights into the development of plant diversity.

References

Gnetophyte Britannica

https://www.britannica.com/plant/gnetophyte 

Plants of the World Gnetum Kew Royal Botanic Gardens

https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:17272-1

Acevedo-Rodríguez, Pedro. (2020) Guide to Genera of Lianas and Climbing Plants in the Neotropics Gnetaceae Smithsonsian National Museum of Natural History

https://naturalhistory.si.edu/sites/default/files/media/file/gnetaceae.pdf

Gong, Yan-Bing. Yang, Min. Vamosi, Jana C. Yang, Hong-Mei. Mu, Wei-Xue. Li, Jiao-Kun. Wan, Tao. (October 19, 2015) Wind or Insect Pollination Ambophily in Subtropical Gymnosperms Gnetum parvifolium (Gnetales). Plant Species Biology

https://esj-journals.onlinelibrary.wiley.com/doi/10.1111/1442-1984.12112