According to Brain (1920a), adult female about 6 mm long (longest specimens reach 8 mm); color, when alive, light green with narrow margin of pale dull green yellow. The dorsum is relatively transparent, giving the insect the color and appearance of the leaf, the green body corresponding with the leaf and the yellowish margin with the midrib or edge of the leaf. Occurring on leaves.
Marsipococcus proteae is similar to M. durbanensis (Brain) by having 2 club-shaped setae adjacent to each spiracle and stigmatic cleft deep and sclerotized. Marsipococcus proteae differs by lacking tubular ducts (present near anal plates on M. durbanensis) and by having peroperucular pores in 2 mediolateral clusters near junction of thorax and abdomen (arranged in conspicuous narrow band anterior of anal plates on M. durbanensis).
U.S. quarantine notes
This species was intercepted 8 times at U. S. ports-of-entry between 1995 and 2012, with specimens originating from The Netherlands, and South Africa. Interceptions were mostly taken on the leaves of Protea and Leucadendron. ScaleNet lists only Protea as a host, and South Africa as the distribution range. No other species of Marsipococcus have been intercepted at a U. S. port-of-entry.