Hi Jim,
There is a problem in clearly identifying all Amaryllis belladonna varieties from some of their hybrids. This is because there has been backcrossing between the species and hybrids, and even segregates between hybrid crosses have throwbacks that retain many species characteristics. The only characteristics that seem to be found in the majority of Amaryllis species is a smaller flower count, many thinner, often channeled sprawling leaves, and the propensity of all the flowers to open facing the location of the mid day sun.
It also seems evident from the colour prints and descriptions of many of the early oddly - often beautifully and uniquely coloured Amaryllis cultivars that were collected from South Africa (over the past three centuries) that a few natural hybrids between Amaryllis and Brunvigia's existed and inevitably some of their genes over eons crossed over into a few local Amaryllis populations in SA.
Bulbs of Amaryllis flower forms that were different in colour and showed other favourable attributes were sent to collectors in Portugal, England, Holland,France, Australia, Brazil etc. I know that David Fenwick is well advanced on a project to trace the history of significant early Amaryllis cultivars in all those countries.
The only certainty (almost a certainty) is that all the hybrids and cultivars we are discussing arose from Amaryllis seed. The xAmarygia from various Brunsvigia species seed parentage which can be found in Australia, all show very strong traits of their Brunsvigia parentage and are quite different in flower shape, colour and flowering ecology from those xAmarygia that have developed from Amaryllis seed and we know colloquially as Amaryllis hybrids.
Cheers
Jim Lykos
Blue Mountains
Australia
Zone 10