shaved horse fly

not listed

N5 - Secure

not listed

Shaved horse fly is a small horse fly. It occurs on the northern United States from Maine to Minnesota, south to Illinois and North Carolina, and in Ontario. It is uncommon in Minnesota, where it is at the western extent of its range.

Adults are stout-bodied and 7 ⁄16″ to ½″ (11 to 13 mm) in length.

There are two large compound eyes on the side of the head and three simple eyes (ocelli) in a triangle at the top of the head (vertex). On the male the compound eyes meet at the top of the head. On the female they do not. The inner upper corner of the compound eye on the female forms a right angle. The antennae have three segments, the scape, the pedicel, and the flagellum. The scape is only slightly longer than wide, the pedicel is much shorter than wide, and the flagellum has many ring-like segments (annulated).

The abdomen is black. The sides are sometimes pale but are never orange. The rear margin of each segment has a fringe of grayish hairs that sometimes expands into a triangle in the middle. The first segment is deeply notched at the middle of the hind margin.

The wing is clear and faintly tinted. It does not have dark markings and is not darkened at the base or at the tip. The cell at the leading edge (costal cell) is clear. At the base of each wing there are two small, rounded lobes (calypters) that cover the halteres. The calypters are large and unequal in size.

The legs are reddish-brown to dark brown. The fourth segment (tibia) of the hind legs have large spurs at the tip. The last part of the foot (tarsus), corresponding to the foot, has three pads.

Total length: 7 ⁄16″ to ½″ (11 to 13 mm)

Late July to September

Females feed on mammalian blood. Males feed on flower nectar.

Sources

24, 27, 29, 30, 82, 83.

Infraorder
Orthorrhapha was historically one of two infraorders of Brachycera, a suborder of Diptera. However, Brachycera did not contain all of the descendants of the last common ancestor (paraphyletic). It was split into five extant (still existing) and one extinct infraorder. Orthorrhapha is now considered obsolete and has not been used in decades, but it persists in printed literature and on some online sources. A recent revision of the order Diptera (Pope, et al., 2011) revived the name Orthorrhapha, but this has not been widely accepted.

Location: Albany, NY

Location: Slinger, Wisconsin

Location: Cass County