Only two cecidosid species (Cecidoses eremita Curtis and E. minutanus) induce external, spherical galls on Schinus branches [14, 22, 23]. Although similar in shape, these galls can be distinguished by their general size, wall thickness and operculum shape. Those of C. eremita are larger and have a thicker wall; they have double the diameter and thickness of those of E. minutanus ([22]; for precise dimensions, see Loetti et al., [24]). The operculum in C. eremita looks like a stopper that was described by Curtis [26] as "…having the diameter of the inside less than that of the external surface, which forms a broader rim". This characteristic allows prompt separation of these galls independently of their general size, since by contrast the operculum of E. minutanus looks like a thin, flat cover (S1 Fig).

"The galls of C. eremita and E. minutanus, named "matecitos" or "tabaneras" by inhabitants of Buenos Aires Province, are globose stem galls and smooth surface and glabrous. The colour is firstly green and brown later. They have a single spherical larval chamber, and an operculum that can be open or closed when it is covered by an opercular cap (see Figure 1). These galls are found in large numbers in the branches of Schinus longifolius (Lindl.) Speg. (Jörgensen 1917)." (Loetti et al., 2016.)