snow fly

not listed

not listed

not listed

Snow fly is a small, wingless, limoniid crane fly. It occurs in North America mostly from Nova Scotia to Ontario, south to Massachusetts and Minnesota, with outlying records in Alberta and Virginia. It is found in woodlands from September through May, but is most active in October to November and February to March. Though believed to be common, it is rarely seen due to its unusual habits. It lives on the ground. It is most often seen on sunny winter days walking on snow near a tree trunk or stone that is warmed by the sun, thus creating an opening in the snow where the insect can emerge.

Snow fly was originally described in by its discoverer 1841. Few other descriptions of it can be found. Adults are brownish-yellow and ⅛″ to 3 ⁄16″ (3.5 to 5 mm) long, not including the legs. They look more like spiders than flies.

The head is small and hairy. The antennae have 7 or 8 segments. The first two segments are thick. The remaining segments are slender and are covered with hairs.

There are no wings but there is a pair of yellow balancing organs (posiers) at the rear part of the thorax. The female has a long, sword-shaped “borer” at the end of the abdomen. The male has a pair of large claspers at the end of the abdomen.

The legs are long and somewhat paler than the body. They are covered with short hairs. On males the third segment (femur) of the hind leg is thickened.

Body length: ⅛″ to 3 ⁄16″ (3.5 to 5 mm)

Woodlands

September through May

The female uses its borer to deposit eggs into the ground.

Sources

24, 29, 30, 82.

Though believed to be common, there are relatively few records of snow fly since its discovery in 1841.

Location: Fairview Twp, Cass County

It warmed up into the mid 30's today. As we walked through the deep snow we often found what looked to be fleas in the animal tracks. After observing this over and over we came to a hole in the snow with a spider crawling out of it. It was eating the pinpoint size 'fleas'.