In many orchid species the labellum is of similar length to the dorsal sepal but in some species the labellum can be shorter or longer than the dorsal sepal. Look at the labellum length from the base to tip and exclude the hinge or basal stalk.
Longer: the labellum is longer than the dorsal sepal.
More or less equal: the labellum is a similar length to the dorsal sepal.
Shorter: the labellum is shorter than the dorsal sepal.
