Dung fly (Scathophaga furcata) https://karits.eu/index.php/2025/11/18/dung-fly-scathophaga-furcata/

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While the Yellow Dung Fly (Scathophaga stercoraria) is the most famous species in this group, S. furcata is also common, particularly in North America (where S. stercoraria is less dominant) and the Palearctic region.

Here is a deep review of Scathophaga furcata:

🔬 Lesser Dung Fly (Scathophaga furcata) Deep Review

1. Classification and Identification

Feature	Detail
Order/Family	Diptera (True Flies) / Scathophagidae (Dung Flies)
Size	Medium-sized fly, typically around 5.0–6.0 mm in wing length (slightly smaller than the famous Yellow Dung Fly).
Coloration	Tends to be a dull yellow or yellowish-brown color, which provides less contrast and is less “furry” than the bright, golden-yellow males of S. stercoraria.
Key Distinguishing Marks	Generally has yellow legs (or pale legs), except for a dark mark or stripe on the outer side of the front femora (thighs). The antennae are typically orange-red but dark at the tip. The cross-veins on the wings are often darkened.
Sexual Dimorphism	Both sexes are relatively similar in color (dull yellow/brownish), unlike the stark difference between the brightly yellow, hairy male and the duller, greenish female S. stercoraria. The arista (part of the antenna) is typically almost bare.

2. Distribution and Habitat

Distribution: Found widely across the Palearctic (Europe and Asia) and Nearctic (North America) regions. It is often the dominant Scathophaga species in parts of North America.
Habitat: As a generalist, it occupies a wide variety of habitats where mammalian dung is present, including:
- Grasslands and meadows
- Woodlands and forest edges
- Wetland areas
- Agricultural and cultivated fields

3. Life Cycle and Ecology

Like other members of the genus, S. furcata plays an important ecological role as a scavenger and nutrient cycler.

A. Larval Stage (Dung Consumer)

Breeding Site: Females lay their eggs directly into the fresh dung of large mammals (e.g., cattle, horses, sheep).
Larval Diet: The larvae develop within the dung, feeding on the decaying organic matter. This process contributes significantly to the decomposition and cycling of nutrients in pasture ecosystems, preventing the accumulation of dung.

B. Adult Stage (Predator and Scavenger)

Adult Diet: Adult Scathophaga flies are predatory and require protein for reproductive maturity. They prey on small insects, catching them on the wing or ambushing them on leaves and flowers. They are also known to feed on nectar and tree sap.
Behavior: Adults are often found resting on vegetation, waiting for prey, or near dung piles for mating. Peak activity is generally from April to August.
Prey Item: S. furcata is ecologically significant as a prey item itself. For instance, the larvae and adults are known to be a significant part of the diet of nestling snow buntings and other small birds, especially in northern latitudes.

4. Comparison with S. stercoraria (Yellow Dung Fly)

S. furcata is often studied alongside the highly visible Yellow Dung Fly (S. stercoraria), which serves as a classical model for evolutionary ecology (especially mating behavior and sperm competition).

Feature	S. furcata (Lesser Dung Fly)	S. stercoraria (Yellow Dung Fly)
Color/Hairs	Dull yellow, less noticeably hairy.	Male is brightly golden-yellow and very hairy/furry.
Size	Generally smaller (4.5–6.0 mm).	Larger (7–13 mm).
Sexual Dimorphism	Less pronounced color difference between sexes.	Stark difference: Yellow male vs. greenish/brownish female.
Leg Color	Pale/Yellow, with a dark spot on the fore femur.	Dark legs (except for pale tarsi).