AbstractIn December 2006, 495 drosophilids belonging to 19 species were aspirated from inflorescences of Calathea monophylla (Vellozo) Körn at a forest reserve in the city of São Paulo, state of São Paulo, and 42 specimens belonging to three species of Drosophila were aspirated from those of Calathea cylindrica (Roscoe) Karl Schumann in an urban forest in the city of Rio de Janeiro, state of Rio de Janeiro, Brazil. In addition, 20 inflorescences of C. monophylla and 14 inflorescences of C.cylindrica were collected and observed for the emergence of flies in the laboratories. In total, 137 drosophilids belonging to Zygothrica dispar (Wiedemann, 1830) plus five species of Drosophila (Drosophila griseolineata Duda and four undescribed species) emerged from C. monophylla inflorescences, and a total of 22 specimens, all belonging to two undescribed species of Drosophila, emerged from those of C. cylindrica. Drosophila calatheae sp. nov., ungrouped but related to both the xanthopallescens Pipkin and the bromeliae Patterson & Stone species groups, is described based on both aspirated and emerged flies from C. monophylla inflorescences from São Paulo city. This new species was also reared in the laboratory with a new medium recipe, thus providing larvae for chromosomal studies.