Background and objectives: Canine filarioids presenting haematiccirculating microfilariae (e.g., Dirofilaria immitis, Dirofilaria repens and Acanthocheilonema reconditum) are the better known worldwide compared to those presenting dermal microfilariae (e.g., Onchocerca lupi and Cercopithifilaria spp.). Filarioids belonging to the genus Cercopithifilaria are reported to infect dogs worldwide; indeed,Cercopithifilaria bainae,Cercopithifilaria grassiiand Cercopithifilaria sp. II sensu Otranto et al. 2013 have been reported from domestic dogs (Canis lupus familiaris) and red fox (Vulpes vulpes). Rhipicephalus sanguineussensulatuis the competent biological vector of these nematodes. Given the lack of data about the infection of dogs in Iran with Cercopithifilaria spp. this study aimed to assess, for the first time, the presenceof infection in this country. Methodology: From October 2018 toJune 2019, skin biopsies of inter-scapular region were collected from489 dogs older than 6 months in Hamedan (n=103),Kermanshah (n=46), Khorram Abad (n=100), Yazd (n=80), Amol (n=80) and Ahvaz (n=80). All of thesampled dogs except for 7 were kept in shelters and breeding centers. Also one golden jackal (Canis aureus) in Hamedan was biopsied. Dermal microfilariae were detected by microscopic examination of skin snips which were soaked in saline solution at room temperature for over 6 hours. The microfilariae species were identified morphologically. Results: Microfilaiae of Cercopithifilaria spp. were found in skin biopsies of 26/489 (5.32%) dogs from Kermanshah (23.91% – 11/46),Yazd (8.75% – 7/80),Hamedan (4.85% – 5/103)and Amol (3.75% – 3/80). No infected dog was detected in Khorram Abad and Ahvaz. Mean length and width of microfilariae were 174.92 μm and 7.64 μm with a rounded head and a short dorsoventrally flattened body (n=21).Based on morphologic and morphometric characteristics ofthe microfilariae, theywere identified as C. bainae with a blunt caudal extremity.No infection was det
