Dilophus serotinus
Loew, 1861
March fly
Dilophus serotinus is a of march fly in the Bibionidae, first described by Loew in 1861. Like other members of the Dilophus, are typically smaller and less robust than related Bibio species, often with reddish coloration. The genus is characterized by a ring of shorter teeth on the front legs rather than the long spurs found in Bibio. As with other bibionids, larvae develop in soil and feed on decaying organic matter.
Pronunciation
How to pronounce Dilophus serotinus: /dɪˈloʊfəs sɪˈrɒtɪnəs/
These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.
Identification
Dilophus serotinus can be distinguished from the related Bibio by the presence of a ring of shorter teeth on the front tibiae rather than long, downcurved spurs. Dilophus are generally smaller and less robust than Bibio, and frequently exhibit reddish coloration rather than black. Males have large, spherical with that meet at the top of the head, while females have disproportionately small heads relative to their body size. Specific identification to species level within Dilophus requires examination of male genitalia characters.
Seasonality
emerge in late season relative to other march flies; the specific epithet 'serotinus' (meaning 'late' in Latin) suggests later compared to . Other Dilophus have been observed in May in Colorado and California, though timing varies by region and species.
Diet
Larvae feed on decaying plant material in rich soils, and have been observed in manure, compost, and on roots of grasses and herbs. mouthparts are reduced and adults do not feed significantly.
Life Cycle
Females use the toothed front legs to dig into soil several inches deep to deposit in masses of 200-300. Larval stages develop in soil, feeding on decaying organic matter. Mature larvae likely overwinter, with occurring in early spring. are short-lived, with some bibionid living only 2-3 days as adults.
Behavior
Males gather in swarms near the ground and low vegetation to attract females. Females approach these swarms to select mates. Prolonged copulation and post-copulatory guarding by males has been observed in related bibionid , with pairs remaining conjoined for hours to days.
Ecological Role
Larvae function as decomposers, breaking down decaying plant material in soils. In some circumstances, larvae can be minor pests of cereal crops, vegetables, and rangeland grasses by feeding on roots. serve as a food source for various .
Similar Taxa
- BibioBibio are larger, more robust, and black rather than reddish; they possess long, downcurved spurs on the front tibiae rather than a ring of shorter teeth. Both are in the Bibionidae and share the characteristic of males having and females having small .
- Plecia nearcticaThe '' flies in copula for extended periods and is a significant nuisance to humans in the southeastern United States; Dilophus are generally less conspicuous and do not form the massive that create driving hazards.