Updated March 26, 2007: Changed from Eucharis × grandiflora to Eucharis amazonica based on the identification from Dr. Alan Meerow (see comments). Thank you, Alan!
Another round of thanks to Darrell (aka “dweeb” on Flickr) of the University of California, Davis, this time for his picture of an Amazon lily via the Botany Photo of the Day Flickr Group Pool (original photograph). Gracias, Darrell!
The × symbol between the genus and the specific epithet for this plant indicates that it is a hybrid between two species. The parent species for Eucharis × grandiflora are thought to be Eucharis sanderi and Eucharis moorei. Where cross-pollination between the two parent plants is possible in the wild, it is also possible that Eucharis × grandiflora may result.
If you're a gardener, here is a factsheet on Eucharis.
The genus Eucharis is native to Central and South America. It has the sad distinction of containing a plant that has become extinct in the past one hundred and fifty years, Eucharis lehmannii.
Botany resource link: The Hebe Society web site not only features plants from the genus Hebe, but also a number of other plants from New Zealand. These include such rarities as the blue-pollened Fuchsia excorticata.