Golden-backed snipe fly

Conservation Status

IUCN Red List

not listed

NatureServe

NNR - Unranked
SNR - Unranked

Minnesota

not listed

Description

Golden-backed snipe fly is medium-sized fly. It occurs in the United States from New Hampshire to North Carolina west to Minnesota and Oklahoma, and in southern Ontario Canada. It is common in the east, uncommon in Minnesota. It is found in deciduous woodlands. Larvae are found in water (aquatic) or in moist, organic-rich soil. They prey on earthworms, soft-bodied insects, or grasshopper eggs. Adults prey on other insects but it is thought that they feed little.

Adults are black with highly contrasting white and gold markings. Females are ⅜″ to ½″ (10 to 13 mm) long, males slightly smaller, ⅜″ to ½″ (10 to 12 mm) long.

The head is black and more or less rounded. There are two large compound eyes on the side of the head and three small simple eyes (ocelli) in a triangle on top of the head. The back of the head is densely covered with long black hairs. On the male the compound eyes are very large and meet at the top of the head. On the female the compound eyes are smaller and widely separated. The antennae have three segments. The third segment is cone shaped, is not divided by rings (annulated), and bears a long, slender style (arista) at the end. The arista is distinctly longer than the antenna.

The thorax has three segments. The upper side is densely covered with short golden hairs. This is the feature that gives the fly its common name. The genus name Chrysopilus translates to “gold hair”. The sides of the third segment (metapleura) are densely covered with black hairs.

The abdomen on the male is narrow and tapered. On the female it is broad and is tapered at least on the lower half. Each abdominal segment is black and has a dense band of silvery-white or pale yellow hairs at the end (apex) except for an interruption in the middle.

The wings appear dark but are mostly clear with prominent black veins. There is a broad, smoky brown border along the leading edge (costal margin). The veins usually have broad borders tinged dark smoky brown. The anal cell is longer than the second basal cell and is closed before the wing margin.

The legs are relatively long and mostly pale. On the front legs the fourth segment does not have spurs at the end. On the hind legs there is just one spur at the end of the tibia.

Size

Male: ⅜″ to ½″ (10 to 12 mm)

Female: ⅜″ to ½″ (10 to 13 mm)

Similar Species

Habitat

Deciduous woodlands

Ecology

Season

Early to mid-spring

Behavior

Adults perch on low vegetation.

Life Cycle

Little is known about the life cycle.

Larva Food

Earthworms, soft-bodied insects, or grasshopper eggs

Adult Food

Insects

Distribution

Sources

7, 24, 30, 82, 83.

Chrysopilus thoracicus (Fabricius, 1805) in GBIF Secretariat (2023). GBIF Backbone Taxonomy. Checklist dataset https://doi.org/10.15468/39omei accessed via GBIF.org. Accessed 6/15/2024.