Hydrotaea is a genus of insects in the housefly family, Muscidae. They occur in most regions of the world but are more populous in warmer climates. They are often found on feces in summer months, and are therefore generally found in close proximity to livestock. Among the 130 known species in this genus, one of the most commonly recognized is the dump fly.[3]
Along with many others genera in the family, Hydrotaea is of forensic importance in both the economic and public health scene. Flies in general are considered by many authorities to be the most important insects involved in human and veterinary medicine.[4]Certain Hydrotaea species have been proven to carry and transmit certain diseases to warm blooded animals, including humans.[5] Researchers continue to monitor these vectors of disease as they have been connected with the spread of mastitis.[6]
Larvae of this genus are often dimorphic obligate carnivores. The second and third instars are predators, and the first is also carnivorous in some species. Some species have cannibalistic final instars. The smallest larvae are under 6 mm[9] and the largest are up to 16 mm.[10] The abdomen has ventral welts and large spiracles with sinuate slits.[3]
Adults commonly feed on the blood of mammals. They are able to reopen wounds that are almost completely healed. Mouthpart morphology in the genus ranges from sponging mouthparts to mouths with rasping teeth. Many species have enlarged prestomal teeth. The metathoracic spiracle is covered in long, thick setae.[10] The average male Hydrotaea is 6.5-8.5 mm and the average female is 5.75-7.5 mm. They are very light brown to bluish black with large, red eyes and plumose antennae.
Flies in this genus are found in the warmer parts of North and South America, Europe, Asia, and Australia. They are most commonly found in urban settings. They are attracted to fermentation and are often found in vegetation, feces, and decomposing carcasses, mainly those dead longer than ten days.[3]
The life cycle of Hydrotaea rostrata has been studied in the field of forensic entomology. Mature flies seek out decay, preferably in material that has been dead for an extended amount of time. Masses of maggots, which are often characteristic of other species of flies, are not typical of H. rostrata. The larvae of this species progress through three stages, or instars, which are then followed by the formation of a pupa. The adult fly emerges from the pupa. The developmental process from egg to adult takes between 518.4 and 1555.6 hours, according to one study in Australia. Development is more rapid in warmer temperatures of 19–30 °C (66–86 °F). In cooler temperatures of 12–18 °C (54–64 °F), development may take up to 64.5 days.[11]