A study of the Floral Biology of Victoria amazonica (Poepp.) Sowerby (Nymphaeaceae)

Abstract

A field study of the floral biology of Victoria amazonica (Poepp.) Sowerby (Nymphaeaceae) was made for comparison with the many studies made in cultivated plants, of Victoria in the past. In the study areas in the vicinity of Manaus, four species of Dynastid beetles were found in flowers of V. amazonica, three of the genus Cyclocephala and one of Ligyrus. The commonest species of beetle proved to be a new species of Cyclocephala and was found in over 90 percent of the flowers studied. The flowers of V. amazonica attract beetles by their odour and their white colour on the first day that they open. The beetles are trapped in the flower for twenty-four hours and feed on the starchy carpellary appendages. Observations were made of flower temperature, which is elevated up to 11°C above ambient temperature, when the flower emits the odour to attract the beetles. Observations on beetle frequency, the number of floral parts, seed dispersal and the evolutionary development of cantharophily are also presented.

Ancestral traits and specializations in the flowers of the basal grade of living angiosperms

“…The second set includes partial syncarpy, an increase in ovule number, and prominent lateral laminar diffuse placentation (presumed to be related to the dorsal placentation seen in Cabombaceae), combined with a switch from carpel sealing by secretion to sealing by postgenital fusion. In pollination biology there is a shift from generalized pollination to pollination by large beetles (Cyclocephala Dejean, Scarabaeidae; Prance & Arias, 1975;Prance & Anderson, 1977), concomitant with a change from diurnal to nocturnal flowering, which occurs in Victoria and several tropical Nymphaea species. The clades with these extreme specializations are highly nested in the family and therefore relatively young (Yoo & al., 2005;Borsch & al., 2008;, although fossil evidence for the presence of crown group Nymphaeaceae in the Early Cretaceous (Friis & al., 2009;Doyle & Endress, 2014) indicates that diversification of the family was not as recent as inferred by the molecular dating analysis of Yoo & al.…”

A polinização e sua relação com a termogênese em espécies de Arecaceae e Annonaceae da Amazônia Central

“…A produção de calor pelas flores (termogênese) é um processo que se desenvolveu também em outras famílias de plantas, entre elas as Araceae (Leick, 1915;Nagy et al, 1972;Meeuse, 1975;Gottsberger & Amaral Jr., 1984), Aristolochiaceae (Vogel, 1990), Cyclanthaceae (Drude, 1877;Knuth, 1904;Gottsberger, 1991;Eriksson, 1994), Nymphaeaceae (Valia & Cirino, 1972;Prance & Arias, 1975), Cycadaceae (Kraus, 1896) e Zamiaceae (Tang et al, 1987). Em várias espécies dessas famílias também ocorre polinização por coleópteros.…”

Cretaceous flowers of Nymphaeaceae and implications for complex insect entrapment pollination mechanisms in early Angiosperms

“…This finding suggests the possibility that shrinkage associated with this particular mode of preservation may have been even more dramatic than the Ϸ50% that has been observed experimentally (39). If, as suggested by complex and congruent floral morphology, the mode of insect pollination was essentially similar to that of modern Victoria, then the pollinators of Microvictoria were small beetles (Coleoptera) and the complex floral chamber effected a trap and release mechanism as in modern Victoria (40). It is likely that, in the first phase of pollination, as in modern Victoria, beetles entered the floral chamber through the apical pore formed by the infolded staminodes, presumably attracted to an odor produced by flower.…”