In the present article the life history and biology of the pierid butterfly Catasticta philothea (Felder & Felder) from the Eastern Cordillera near Bogotá, Colombia is presented. The larval stages from egg to fifth instar larva and pupa of Catasticta philothea are described as well as larval and adult habits and habitat. The female of this species is also illustrated and described for the first time. The article terminates with a discussion of food plant data for the Catasticta group. What is unusual about the biology of Catasticta philothea is that this is the first time in which the larval food plant for this genus is confirmed as not being a mistletoe, but a tree belonging to the family Melastomataceae. In the course of the study, a number of experiments and observations were carried out in an attempt to determine why this should be the case, but with inconclusive results.