The case of Cattleya mendeli (ancient) and Cattleya mendelii (modern).
 

To all Cattleya fans. :waving

I have the pleasure to grow one clone of each of C. mendeli and C. mendelii ...

What the heck is the difference one letter 'i' makes in a Cattleya name ? In case of mendeli vs mendelii . the flowers of both are distinctly different , and it is to me , and only to me , NOT the case of a synonym.

I speculate that my individual specimen of C. mendeli must be 150+ years of age , which fact(?) fills me with awe ,
kind of ... I like to think that this specimen could be the only one left on earth from the old days , which would make it irreplaceable. (smile)

And though my clone of [C. mendelii Carlos Arango] shares in the judgement as one of the best 'modern' C. mendelii ,
see below , it could be easily replaced if lost.
Cattleya mendelii Dombrain – Unifoliate Cattleyas

The eminent Arthur A. Chadwick has explained everything nicely , including photos , see here ::
Cattleya mendelii

Needless to say , I care for this my specimen of C. mendeli with special attention. When the buds are out of the sheath and growing in bulk , I hang the plant every night in a safe place to prevent those big locusts from getting at them. (smile)

I'd love to see some comparison photos showing both of them in bloom!

The case of Cattleya mendeli (ancient) and Cattleya mendelii (modern).
 

I am a bit of a pedantic perfectionist , and I do not do photos of orchid blooms , because they cannot transmit the
vivid beauty of the natural flowers. For this reason , I have no 'stock photos'.

But I do appreciate the logic and the wish for comparison photos in this case , and I will provide.

However , as both plants just had their annual flowering , we need to wait for a little while , sorry. :bowing