I hope I'm posting this in the right place. I just came across the term "sensu" with regard to Cattleyas and Google is not being very helpful here. Can anyone help me understand this term?
That does help some - thanks! It seems that it refers to the generally accepted organization of genus and species at a given time. This Cattleya Wikipedia article uses the term along with Roman numerals like Sensu MCMXCIX. So that would refer to the way Catts were organized in 1999. Right? I think talking through this is helping.
Exactly. Sensu is the Latin ablative case meaning 'in the sense of' or 'as decribed by' or 'as described in'.
So the Wiki article says 'what was named Sophronitis... or Laelia in the year 1999'.