Mexico is a diversity center for Bombyliidae, the seventh most diverse family within Diptera. Bombilids are important because some species are pollinators and other are parasotoids so they control other insect populations and have potential for being used for plague control. This study pretends to describe the diversity of Bombyliidae in Quilamula, Morelos, located in the reserve Sierra de Huautla. The field work was made during twelve months between 2003 and 2004, using aerial net and Malaise trap. Methods for species richness estimation were applied, like species accumulation curves and non-parametric models. Ninety seven species were captured from which five are new registers for Mexico and twelve new for Morelos. Clench's is the species accumulation model which best fits to the data, over exponential and logarithmic models. Clench model estimates 113 species in the study area, from which it was collected the 85.7%. The non-parametric models ICE, ACE, and Chao2 subestimates diversity and Jack-Knife 2 gives and estimate close to the Clench model estimate. ICE and Chao2 are the non-parametric models which best perform. The species richness is greater in rainy season with the maximum in October, although abundance is greater in dry season with the maximum in March. Temporal distribution and habitat preference of species agrees with parasitoids and flower-loving habits of Bombyliidae. Some behaviors observed during the field work are described, in particular what appears to be territorial and mate behaviors. An illustrated key for the genera and some species founded are presented. The study area is recognized as a diversity center for Bombyliidae.
