Hesse (1969) redescribed this species as follows: Body with the yellowish reddish or yellowish brownish distributed in the same way, but base of thorax above without extensive yellowish reddish; middle part of metanotum distinctly more broadly black; sides of tergites 1-5 distinctly less extensively yellowish, confined more to sides and not enveloping bullae on sides of 2 and also not extensively occupying sides apically on 1-3 as in C. fascipennis; hind margin of tergite 1 yellowish or yellowish reddish only on extreme sides, and those of 2-4, and to a certain extent also 5, only narrowly whitish, this whitish not bordered on basal sides with conspicuous orange-yellowish, and almost only extreme apical corners on sides of 5-7 whitish; bullae darker brownish ; base of venter not so pale yellowish, darkened, more castaneous brownish; hypopygial structures below and sternite 8 more uniformly or extensively reddish brownish; legs with the tibiae and tarsi more brownish than yellowish, and front and middle femora appearing more extensively brownish above, and hind femora more uniformly or more extensively darkened, the base and lower surface not so pale yellowish, the spines on them below darker, more blackish. Integument of thorax above slightly more coarsely rugulose; that of metanotum distinctly more coarsely rugulose; that of abdomen above dull, not shining as in C. fascipennis and related species, and with coarser and much denser granular setiferous puncturation. Vestiture with the hairs on vertex and basal half of frons slightly deeper yellowish, more yellowish reddish; those on thorax above in four streaks comparatively denser, distinctly more fulvous reddish, those along the two submedial, discal streaks appearing darker or more reddish mauvish in certain lights; rest of longish hairs, excepting whitish ones on propleural part, front coxae and in tuft at extreme sides basally on tergite 1, tinted more yellowish or fulvous in certain lights; those on middle and hind coxae and base of hind femora also more yellowish not whitish; depressed hairs in fine granular aciculate puncturation on abdomen above distinctly much denser and more fulvous or yellowish; hinder part of tergites with scarcely perceptible, narrower, or more obscure, greyish tomentum, not so conspicuously evident as broadish whitish bands as in C. fascipennis. Head with the antennae distinctly shorter, very much shorter than thorax (excluding scutellum), only about 3.06 mm long; segment 3 and club proportionally shorter, the latter distinctly more subpyriform; proboscis about 6.4 mm long. Wings, relative to body, shorter than in C. fascipennis, with a very similar pattern, the dark however occupying more of basal part of first posterior cell, and also with more distinct, or darker, fuscous borders along posterior vein of discoidal cell and basal cross veins of third posterior cell; veins darker; alula comparatively larger. Legs with the thickened hind femora not only armed below with a double row of spines, but also laterally and dorso-laterally in apical half with some distinct spines, entirely absent in C. fascipennis; hind tibiae with distinct spicules on lower apical part, or apical third, minute or absent in C. fascipennis. Hypopygium with the lobes of tergite 9 slightly more narrowed and pointed apically; processes of sternite 9 proportionally much smaller, shorter, their broadened, apical, spoon-shaped part comparatively less broad. Length of body: about 18 mm, Length of wing: about 12 mm.

It differs from the female of C. fascipennis in the less smooth and shining, more punctured dorsum of the abdomen above which has more fine hairs, and the more coarsely transversely wrinkled last three segments; comparatively narrower yellowish or dirty yellowish hind margins of tergites 1-4; shorter hairs on legs; comparatively less thickened hind femora; darker veins in comparatively shorter wings, of which the alula is slightly larger and broader; and the less extensive yellowish reddish across base of thorax above.

Type locality: 'Africa australis' (= South Africa).

The information below was extracted from Hesse (1969): The true identity of this species is difficult to ascertain without an examination of the type specimen itself. Its recognition is rendered more difficult owing to the fact that several of the known species, with a fascipennis-type of wing pattern, show more or less uniform characters, especially in this type of wing pattern and even in the genitalia. From Gerstaecker's description, though fairly comprehensive, C. umbrina cannot be identified satisfactorily because the author based it on a single male specimen and it may be made applicable to some of the other related forms unknown to Gerstaecker. Bequaert has given a detailed redescription in 1963 of what he took to represent C. umbrina, but as I have indicated under C. fascipennis his description is more applicable to specimens which probably represent the latter species than to C. umbrina s.str. in which the antennae are stated by Gerstaecker to be 'merklich kurzer als der Thorax' and the abdomen above to be 'durchaus matt', characters not present in Bequaert's specimens nor in those assigned by me to C. fascipennis Macq. A single male specimen, with dull abdomen and antennae which are distinctly shorter than the thorax, in the collections of the Transvaal Museum, agrees inessential features with the description of C. umbrina given by Gerstaecker and to which species it is referred provisionally.

South Africa.

The species was collected in the southwestern parts of the Cape, Malmesbury (A. Gobreghts, Nov. 1928) (Hesse 1969).

The information below was extracted from Cannings and Scudder (2005): Dipterans are primarily aerial insects and the mesothorax, which bears the only pair of wings, dominates the thorax - the prothorax and metathorax are greatly reduced. The legs are normally rather simple and are used primarily for perching; in some groups, they are modified for prey capture or for signaling during courtship. The tarsi are nearly always 5-segmented. The functional wings are membranous and their pattern of veins is critical in fly classification and identification. During the evolution of flies, there has been a trend towards a reduction in veins, especially in the rear half of the wing – changes that evidently relate to improvements in two-winged flight. The hindwings, present in most other insects, are reduced in Diptera to small, club-like organs, called halteres, used for stabilising flight.

Herbivore - Nectarivore (nectar-eating)

The flies in this family are not known to hunt, catch or prey upon other insects as asilids do. They are however known to imbibe on the flower nectar especially Afroleptomydas and Cephalocera. These species sometimes visit flowers, especially those of species of Mesembryanthemum (Hesse 1969).

Like the others, flies in the Mydidae family begin life as an egg, which hatches into a grub-like larva. Most of the fly life is spent in the larval stage, mainly eating and growing, as well as molting several times. Some flies may spend at least a year as a larva. The next stage is a pupa, during which the insect transforms into its final stage, emerging from the pupa as a winged adult, able to mate and reproduce. In many species, males stake out positions at favourable egg-laying sites and wait for females to arrive (Hesse 1969).

Individuals of this group are mainly collected in August to November (few records in December) (Kirk-Spriggs and Sinclair 2017).

Fynbos