Studies on the development and reproduction of Brethesiella cf. abnormicornis (Girault) (Hymenoptera: Encyrtidae), a parasitoid of the Colombian fluted scale, Crypticerya multicicatrices Kondo & Unruh (Hemiptera: Monophlebidae), were conducted under laboratory conditions. The duration of the life cycle, adult longevity, fecundity, and population parameters were determined. The parasitoid takes about 29 d to complete a single generation (from egg to adult). In addition, population parameters show that one female wasp is replaced by nearly 32 females, with a female-to-male sex ratio of 2: 1. Population parameters estimated in this study can be considered baseline information for a mass-rearing protocol. This is the first detailed study of the biology of a species of Brethesiella, where the duration of all larval stages of the parasitoid is determined, being an important contribution for further biological studies of endoparasitoids.