I would say this is aperfect C. percivalliana s/a....perfect shape, perfect contrast between the white of the flower and the colours of the lip and last but not least perfect intense colouration of the lip.
Always loved the compactness and small size of Cat. percivalliana. If I have to find a defect Is the unpleasant( at least for me) smell she has.
Have had the white form 'oro cochano' with that intense sulphur yellow lip and the s/a 'carache' both from Rio Caura(Venezuela)