I recently had the privelage of having a nice underside view of my usumbara as it was out looking for prey. The coloration of the T is light enough that i can see its booklungs through the pale orange of the underside of its abdomen. In between the two forward booklungs, there is a horizontal white spot(where the epigastric furrow is). That resembles a third booklung(only turned on its side, and on the epigastric furrow). Does this have any use of sexing the T?
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