Tabanids, stomoxyine flies, hippoboscids and tsetse flies are the most well‐known brachyceran biting flies of livestock. Only a few other higher Diptera have developed the unique mouthparts required for blood feeding. These neglected blood feeders can also have direct effects on hosts through blood loss, and are likely to contribute to the transmission of pathogens. Musca crassirostris (Diptera: Muscidae) is one of the most abundant of the muscid flies with this haematophagous lifestyle; it is widespread in the Palaearctic, Afrotropical and Oriental regions. The present study reviews and summarizes the biology and morphology of this species, and its potential for impact on animals and humans. The study also provides a fully illustrated description of the fly to facilitate its identification, and reviews information on abundance, with a focus on recent trapping surveys in Thailand. When sampled using traps designed for other biting flies, M. crassirostris appears to be four and 45 times more abundant than stomoxyines and tabanids, respectively. High numbers of M. crassirostris in the vicinity of livestock have also been associated with outbreaks of disease, such as that of a fatal plague in bovine farms in Egypt. This calls for a reconsideration of its potential impacts on livestock economics and health, and thus the development of suitable control methods.
Musca crassirostris belongs to a group of true obligate blood feeders that are highly prolific and abundant around cattle.
Its mentum is a boat‐shaped, black, shiny mass of chitin, and its labella harbours rasping prestomal teeth that are greatly increased in size and strength compared with those in other Musca spp.
Based on captures in haematophagous insect traps in a livestock area, the abundance of M. crassirostris appears to be four and 45 times greater than abundances of stomoxyines and tabanids, respectively.