University of Alberta Museums Search

Adult females are 8-11 mm long, mainly black, with patches of white pruinosity (powder) and hairs (Teskey 1990). On the head, the antennae are slender, with the first three segments yellow, the remainder black; the frons is nearly square; the clypeus is glossy black, with a shorter median pruinose stripe compared to other Chrysops; the palpi are black. The thorax is covered with mainly white hairs, with sparse black hairs and two indistinct parallel stripes on the scutum; the notopleuron has dominant black hairs; the legs are black, with paler mid and hind tarsi; the wings are infuscated moderately. The abdomen is black dorsally and ventrally, with faint median pruinose triangles on tergites 1-2 (Teskey 1990). Males are similar but even more pigmented, and they have black hairs all over except for apical abdominal segments (Teskey 1990). Chrysops mitis can be difficult to distinguish from C. ater, but the wing cell cua1 is infuscated at its base in the former and is hyaline (transparent) in the latter (Teskey 1990). Larvae are cylindrical, elongate, fusiform (spindle-shaped), creamy white to pale yellow, frequently with a greenish tinge, and 16-18 mm long. They are virtually indistinguishable from the larvae of Chrysops cincticornis (Teskey 1969).

Little is known about the specific life history of C. mitis. White et al. (2000) did find that C. mitis is a strong flier, with a minimum dispersal rate of 1.2 km/hr, which was second only to Chrysops ater and well above the remainder of the deerflies. Lake and Burger (1980) discovered that C. mitis is an obligate anautogenic species, meaning that females must take a blood meal before producing their first batch of eggs; many tabanids are facultative autogenics, meaning that they can produce their first batch of eggs without a blood meal if conditions are right. Adults of C. mitis prefer to fly in the morning than the afternoon, and prefer open field habitat to the edges of wooded areas (Ossowski and Hunter, 2000). Males of C. mitis prefer to find females by waiting on shrubby vegetation at the tops of geographical summits and pursuing passing flies (Leprince et al., 1983). Eggs are laid in triple or quadruple-layered masses of about 550 eggs; the masses are about 8.8 mm in length, 3.4 mm in width, and 1.6 mm in height. The eggs themselves are dark brown to black and are about 1.5 mm in height (Iranpour et al. 2004).