Unfortunately so called Epiphyllum hybrids are rather like roses. Far too many names for plants that have similar flowers and were not worth naming as something new. Though one has to say at least the rose growers will raise several thousand seedlings before picking out one to name and then destroy all the rest. I often get the impression the Epiphyllum hybridisers want to give a different name to every seedling they raise, whether worthy of one or not.
If you click on the pictures in this "Red Epiphyllum" link you will find often two flowers that look little different but have received different names, plus many are not that different from the old "ackermannii hybrid":-
https://www.google.co.uk/search?q=red+e ... DMs#imgrc=_" onclick="window.open(this.href);return false;
I wonder how many raisers of hybrid Epiphyllum's follow these recommendations. Many Epiphyllum namers do not realise that just as with species there is an International Code for naming cultivated plants, unfortunately the incorrectly named ones do not get reduced to synonymy like species:-
http://www.hortax.org.uk/rules-of-naming.html" onclick="window.open(this.href);return false;
http://www.epiphyllums.org/Guidelines" onclick="window.open(this.href);return false;
http://www.ishs.org/sci/icraname.htm" onclick="window.open(this.href);return false;
I wonder just how many so called Epiphyllum hybrids on sale follow the international rules for cultivars and have been correctly published, let alone registered? I doubt many professional nurserymen realise there is an International Code for cultivated plants, let alone amateurs producing their own hybrids and naming them.
