Is E. oxypetalum
viviparous? Some of the Epiphyllum species are, and they produce quite beautiful fruits that burst with germinating seedlings. There are some good pics of the viviparous fruits/offspring in
this paper:
viviparity in E. phyllanthus
The above article may be interesting to anyone interested in the ecology/evolution of viviparous plants/cacti in general:
Quote:
Vivipary and offspring survival in the epiphytic cactus Epiphyllum phyllanthus (Cactaceae) -- Cota-Sánchez and Abreu, 10.1093/jxb/erm232 -- Journal of Experimental Botany
Our data suggest that vivipary is an intrinsic reproductive mechanism favouring the germination and dispersal of the fittest offspring regardless of substrate and environmental conditions. Even with the expensive metabolic costs involved in viviparous reproduction, the proportion of the fittest individuals able to establish successfully during the early stages, though relatively low, is equivalent in the two lots under natural conditions. Therefore, germination is not a limiting factor in the perpetuation of viviparous species, but seedling establishment is. In viviparous individuals of E. phyllanthus seedling mortality during the acclimation and establishment phases rather than failure to germinate within the fruit appears to be one of the limiting factors affecting local population density.
In conclusion, the incidence of vivipary in phylogenetically distinct lineages of the cactus family is evidence of a parallel directional change towards a more practical reproductive mechanism. In other words, it is a reproductive advantage that, in addition to allowing propagules to root and grow almost immediately, favours quick establishment whenever seedlings land on suitable substrates.
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