part_of area dorsal mesopostnotal flange HAO:0000258 The area that is more heavily sclerotised than surrounding areas, traverse the mesopostnotum, unites laterally with the dorsal mesopostnotal flange, continuous laterally with the laterophragma and dorsally (anteriorly) with the pseudophragma and is located anterior to the ventral mesopostnotal flange. mesopostnotum