no pollinators have been reported in the literature for Syngonium
species, there seems to be little doubt that the genus has the same
type of pollination syndrome already known for Philodendron,
Dieffenbachia (Croat, 1978), and Xanthosoma, which are known
to be pollinated by large awkward scarab beetles of the subfamilies
Rutelinae and Dynastiniae. T. Ray (pers. comm.) reports that S.
triphyllum is pollinated by the genus Cyclocephala (Dynastiniae)
in Costa Rica. In such cases the behavior of the spathe and spadix
are important and in all probability Syngonium is thermogenetic
in the same way as Philodendron (Sheridan, 1960), Monstera
(Sheridan, 1960; Madison, 1977), Symplocarpus, Arum,
Arisaemum, Amorphophallus, Biarum and Sauromatum
(James & Beevers, 1950; Smith & Meeuse, 1966; Knutson, 1972).
In these cases it has been shown that temperature increase in the
spadix is due to rapid oxidation of starch (James & Beevers,
1950; Beevers, 1950; Hatch & Millard, 1957; Hess & Meeuse,
1968a, 1968b; Knutson, 1974; Nagy et al., 1972).
of Syngonium are markedly protogynous, becoming receptive
1-2 days before the staminate flowers shed pollen. They are already
receptive by the time the spathe opens. At this stage the spathe
is broadly opened and access to the pistillate flowers is easy.
Presumably pollinators enter the spathe at this time and visit the
pistillate flowers while the staminate flowers are not yet open.
Usually, by the beginning of the second day the pollen has begun
to emerge in stringy masses from between the synandria, and the
pistillate flowers are no longer receptive. By this time the spathe
tube is much contracted and nearly closed, perhaps forcing an entrapped
beetle to crawl over the pollen-covered spadix, as in the case of
Dieffenbachia (Croat, 1978).