As with Ephedra and Welwitschia , Gnetum is pollinated by insects.
Several features suggest this: pollen is not produced in large volumes; both male and female strobili are aromatic (the odor varying with species from sweetish to putrid); and strobili typically open in the morning, or in some species in the evening.
The genus has been subdivided by Markgraf (1930, in Carlquist 1996b ) as follows: About 19 species of Asian and Indomalesian lianas, incl. Seeds drupelike, enclosed in a red, orange, or yellow, fleshy (rarely corky) false seed coat; female gametophyte tissue copious, succulent. The following species are found in Malesia or SE Asia ( Carlquist 1996b ): Gnetum costatum, G. Gnetum ridleyi Gamble is restricted to a small area in Pahang, Malaysia (Markgraf 1930, in Carlquist 1996b ). gnemon , and as the remaining species of the genus are all woody vines, they are presumably not usable in dendrochronology. "Lignans are of the guaiacyl-syringyl-type; the antiasthmatic properties for which G. The mechanism of such horizontal gene transfer remains unknown, but Won and Renner (2003) state that "agents that have been implied are viruses, bacteria, fungi, and plant cell-piercing insects," all of which have been implicated in other instances of horizontal gene transfer. Gnetum leptostachyum Blume and Gnetum montanum Markgraf are listed as threatened in Viet Nam by the World Conservation Monitoring Centre . The mountain is an isolated volcano south of the Central Divide. Conspectus Regni Vegetabilis: Secundum Characteres Morphologicos Praesertim Carpicos in Classes Ordines et Famillas Digesti , p. Proceedings of the National Academy of Science 100(19):10824-10829.