Mompha

Abstract: Enlarged or deformed floral tubes of the herbaceous perennial plant genus Cuphea have been noted by many collectors but without knowledge of the causative agent. A survey of herbarium collections of Cuphea found enlarged, thickened or inflated, sometimes exceptionally hairy flowers present in nine species from Mexico, Guatemala, Costa Rica, Panama, and Ecuador. Investigation determined the enlargements were due to two different gall-forming parasites. Cuphea appendiculata, C. cyanea, C. hookeriana, C. llavea, C. nitidula, and C. spectabilis in the dosely related sections Diploptychia, Heterodon, and Leptocalyx are hosts to Asphondylia sp. (Diptera: Cecidomyiidae), a gall midge. Asphondylia is notable for its apparent symbiotic relationship to fungi which grow in the gall. Cuphea bombonasae, C. epilobiifolia, and C. spraguei, of section Heteranthus, are parasitized by Mompha sp. (Lepidoptera: Momphidae), a microlepidopteran that feeds on the reproductive organs of the flower. These are the first records of gall-forming genera parasitizing the Lythraceae and are new host records for the insects. Flowers infected by either parasite produce no seeds. However, the number of infected vs. non-infected plants is relatively low (14% gall midge infection in C. cyanea and 22% Mompha sp. infection in C. epilobiifolia), and among the multi-flowered inflorescences of any plant, at least 80 percent of the flowers remain free of galls, suggesting the gall makers strike a balance in their parasitism that does not excessively threaten the plant species on which it depends.