F. occidentelis (Pegande) was found to be an important pest in chrysanthemum green houses at the Bogota Plateau. We studied its biology under lab conditions (24 ± 2.50C and 66 ± 12% R.H.). Its life cycle was egg 4-5 days, first instar nymph 3-4 days, second instar nymph 5-3 day prepupa 4-6 days, pupa 3-5 days and the adults had a longevity between 60 and 121 days. Females reproduce by parthenogenesis (Arrhenotoky) in the absence of males. Fertilized females produced 87.5% females and 12% males. Fecundity of parthenogenetic females was 325.7 eggs per female. Fecundity of sexually reproduced females was 303.1 eggs per female.