Leslie, I think, that you - for once - are barking up the wrong tree (pardon the botanical pun!
):
christiansonianum is a variety of gratrixianum, which my flower and plant clearly isn't.
In their description of var. annamense, for once, the two preeminent gentlemen, Cribb and Braem, seem to be somewhat in accordance. Cribb in The Genus Paphiopedilum, 2nd ed.: "Var. annamense ... differs from typical P. villosum mainly in its dorsal sepal which is white with a dark violet-purple central streak or blotch edged with pale green or yellow" (p. 258).
Braem et al. in the 2nd ed. of his likewise named monograph states: "The dorsal sepal [of var. annamense] is cream-coloured to whitish and is veined and suffused with dark purple in the centre, with the purple area slightly bordered with green and/or yellow" (p. 192).
Cribb and Braem might be considered lumpers, though, in comparison with Tuan, Gruß et al. in their extensive review of P. villosum in Vietnam in their description of var. laichaunum (Die Orchidee, vol 4(15), 2018). They determine my flower with its lack of a pale green or yellow bordering of the central violet-purple colouring of the dorsal as var. fusco-roseum. I doubt, if all botanist would find this slight colour difference as sufficient to warrant varietal status, though.
I gather that the most exact, almost verging on the fussy, (what germans would call 'akribisch') determining of my plant would be: P. villosum var. annamense fma. fusco-roseum.
And probably, the flower, you had in mind for var. annamense is the var. laichaunum, Tuan, Gruß et al. are describing?
