Body of adult female red, covered by a pliable test that is slightly convex with 10 small lobes around body margin in newly formed tests, but highly convex and rotund in mature tests; test has 3 openings, anal opening for exit of honeydew and crawlers and spiracular openings for respiratory functions, all 3 openings have protruding white wax; tests are either light reddish brown or yellow; individuals coalesce in heavy infestations forming encrustations that may cover entire branches; male's test is elongate and reddish brown with an operculum at posterior apex which is important for exit of the adult. Crawlers and adult males are bright red; males are winged or wingless. Occurring on small branches and twigs. Males are relatively common but apparently are not needed for reproduction.
Kerria lacca is similar to K. ebrachiata (Chamberlin) but differs by having the brachial plate on a cylindrical protrusion (the brachial plate does not protrude on K. ebrachiata).
U.S. quarantine notes
This species was intercepted once at U. S. ports-of-entry between 1995 and 2012, with the specimen originating from Taiwan.Because it remains a source of natural shellac and is transported around the world, we have included it in the key. We have examined specimens taken in quarantine from India on an unknown host. ScaleNet includes hosts in over 20 plant families from the Oriental, Nearctic, and Palaearctic zoogeographic regions. No other species of Kerria have been intercepted at a U. S. port-of-entry.