Altogether 18 species of the families Opetiidae and Platypezidae are reported from Romania, based on newly studied material and previously published records. The following three species are recorded from Romania for the first time: Agathomyiavernalis Shatalkin, 1981, Callomyiasaibhira Chandler, 1976, and Lindneromyiahungarica Chandler, 2001. The presented differential diagnosis and a detailed redescription of body and genitalia of the male of Callomyiasaibhira are based on one specimen which is the first male found in Europe. Information about distribution and biology of all 18 Romanian species is provided as well as photographs of selected important species. Finally, a new checklist of all Romanian species is given.
Keywords: Callomyiasaibhira redescription; Diptera; Opetiidae; Palaearctic Region; Platypezidae; Romania; biodiversity; biology; distribution; new records.