soldier fly

not listed

not listed

not listed

Nemotelus kansensis is a small soldier fly. Flies in its genus are among the smallest soldier flies. It occurs in the United States from New York to Maryland, west to South Dakota and Kansas, and south to eastern Texas. It also occurs in southern Ontario Canada and in Monterrey Mexico. The larvae are aquatic, living in water. They feed on organic matter. Adults are found on flowers near water. They feed on flower nectar.

Females are 3 ⁄16″ (4.5 mm) in length.

The head is long, round, flat, entirely black, and shiny. It is moderately sparsely covered with short, appressed, silky hairs. The front of the face is strongly produced forward, cone shaped. The compound eyes are widely spaced at the top of the head. The antennae are short and black. They have seven segments and are inserted halfway between the compound eyes and the tip of the face. There is a short, bristle-like appendage (arista) at the tip. The tube-like collection of mouthparts (proboscis) is long, black, sharply bent in the middle, and curved on the outer half. The mouthparts are adapted for feeding from the long disk florets of coneflowers.

The thorax is moderately sparsely covered with short, appressed, silky hairs in the middle, more densely on the sides. It is entirely black except for a very thin white line on each lateral margin. It does not have a greenish tinge.

The abdomen is shiny, hairless, and black with white markings. It does not have a greenish tinge. The first segment is short and unmarked. The second, third, and fourth segments each have a white, forward-pointing triangle in the middle. The fourth and fifth segments have a narrow white band on the rear margin. On the fourth segment the white triangle merges with the white band. The second through fifth segments have a continuous, narrow, white stripe on each lateral margin that merges with the band on the rear of the fifth segment.

The wings are clear. The veins are white except for those on the leading (costal) margin, which are yellow. The discal cell is rather large. Four veins extend from the discal cell to the outer margin. The fourth vein originates in the basal third of the underside of the discal cell. The knob at the tip of each balancing organ (haltere) is white.

The third leg segment (femur) is mostly black, yellowish just at the tip. The fourth leg segment (tibia) is black in the middle, merging to yellowish at each end. The last part of the leg (tarsus), corresponding to the foot, is yellowish.

Males are smaller, ⅛″ (3.5 mm) in length. The compound eyes meet at the top of the head. The facial protuberance is shorter and more slender, and there are two small white spots at the base on the upper side. The antennae are inserted at the base of the protuberance. The abdomen is entirely white. The tibia on the hind legs has a black spot.

Females: 3 ⁄16″ (4.5 mm)

Males: ⅛″ (3.5 mm)

Near water

When at rest, wings are held over the back overlapping each other, like a closed pair of scissors.

Organic matter

Flower nectar

Sources

29, 30, 82, 83.

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.

This species has no common name. The common name for the family Stratiomyidae is soldier flies, and it is applied here for convenience.

Fontenelle Forest, a private conservation organization in Nebraska, uses the common name “Kansas soldier fly” for this species. No other source can be found that uses any common name for the species.

Nemotelus kansensis small soldier fly, male with white abdomen

Nemotelus kansensis, soldier fly, on oxeye daisy at Barnes Prairie, Racine Co., WI on June 23, 2022.

Location: Barnes Prairie, Racine Co., WI

Nemotelus kansensis, soldier fly, on oxeye daisy at Barnes Prairie, Racine Co., WI on June 23, 2022.