Cecidomyiidae (Diptera): richness and distribution in the Amazonian forest

Grandez-Rios J.M.; de Araújo W.S.; Maia V.C. · Papeis Avulsos de Zoologia (2026) · DOI: 10.11606/1807-0205/2026.66.025

Resumen

The present study aimed to survey the richness and distribution of gall midge species (Cecidomyiidae) in the Amazon forest. Additionally, we compilated data on the characterization of insect galls and host plant species identification, and developed a taxonomic key of gall midge genera registered in the Amazon forest. For this, data were obtained from the literature, but also from papers containing the original description of each gall midge species. A total of 31 gall midge species have been recorded in the Amazonian forest, with the majority reported in the Brazilian Amazon (29) and two species found in the Peruvian Amazon. The genera Lopesia was the best represented among gall midges. Calophyllaceae were the plant family with the greatest number of gall midge species. Leaves were the most attacked plant organ (74%). Most morphotypes are globoid (75%), green (42%), glabrous (58%), and one-chambered (55%). The state of Amazonas (Brazil) and the department of Loreto (Peru) recorded the highest number of gall-inducing species. Furthermore, 17 gall midges species were described from the Brazilian Amazon, while only two species were described from the Peruvian Amazon. The remaining species (12) were described from other biomes and latter recorded in the Amazon forest. In the 20th and 21st centuries, 13 and six gall midges species were described, respectively, being Rübsaamen and Maia the authors who described the highest number of species. After 1921, there was an 85 years interval without new taxonomic contributions until 2006, when two new species were described from the Amazon forest. The taxonomic key for gall midge genera stands out as one of the few available for distinguishing genera in the Neotropical region, facilitating the work of taxonomists. It is also the first taxonomic key specifically designed for this phytogeographic domain. In order to fill these gaps in the taxonomic information on gall-inducing insect species in the Amazon forest, more efforts are needed in the identification and description of gall-inducing species, particularly within the family Cecidomyiidae.