The issue now is that callosum has 4 named varieties; callosum, sublaeve, warnerianum and vinicolor. How one differentiate between those is anyone’s guess. The designation thailandese was used to group the ones bred from recent Thai discoveries.
On top of this confusion is the barbatum, which looks like callosum, and has a miniature variety nigritum.
The one here I think is the sublaeve type, a smaller version of callosum.
So I flowered this callosum from Sam’s selected plant from the sib (Perfect Circle x Vini Beauty). Sam named it ‘Red Wings’, which is a good descriptor I think. It just opened, so not sure if dorsal will expand more?
The cross is same as one owned by HappyPaph in link below that has fantastic shape and color (any update on your plant HP?):
The dorsal is much narrow than aforementioned but the top petal warts dictates this as callosum fm. vinicolor and not the viniferum (which has warts over entire petal surface), which is now a valid species according to WCSP.
I might use the pollen of my ruby callosum above to sib these together.
And judging from the litterature, I think the taxonomic status of 'warnerianum' can at best be described as debatable: some authors ascribe it varietal status; others see it as a hybridic, intermediate between callosum and barbatum; and the rest - the majority? - sink it into synonymity with the typical variety.
Finally, the very, dark red coloured callosum, that you present above with such a beautifull example, would probably by most botanists these days be considered not a variety, but a colour form, namely fma. viniferum - together with the albino form, fma. viridiflorum.