Carol says its obplicate. But I'm as ignorant as most, so am unsure.
Seemed plausible... thought I'd check the dictionary : I found this quote from a scientific paper....
"The mitral sclerites have four sides known as the accrescent, decrescent, plicate, and obplicate sides, while the four sides of the sellate sclerites are the sella, ........."
Oh dear.... that didn't help, did it?