P. gratrixianum with funny lateral sepals

[JustinR]

Here is my P. gratrixianum finally flowering after a very long recovery process. I had a fire in my greenhouse about 13 years ago and this one barely survived, but now it is doing well and flowering for the first time. These are tough plants!
Anyway, I noticed the lateral sepals are kind of mirroring the dorsal, not only with the markings but also the shape, is this a common trait in gratrixianum?

 

[dodidoki]

Splitted synsepal points back to the ancients.Very nice.

 

[Ozpaph]

split ventral; it happens