flat-footed flies

Platypezinae are small flies, no more than ¼″ (6 mm) in length.

On the female, the upper part of the front of the head (frons) has only sparse, scattered, short, stiff hairs (setae).

On the upper part of the thorax (scutum) of most flies in the Family Platypezidae, there is a row of bristles along the midline (acrostichal bristles), and a row of bristles (dorsocentral bristles) on each side of the acrostichal bristles. On Platypezinae the acrostichal bristles are absent, and the space between the dorsocentral rows of bristles is bare.

The legs are short. On the hind legs, the fourth segment (tibia) and the last part of each leg (tarsus), are dilated. The first tarsal segment is short, shorter than the second through fourth segments taken together, and it is laterally compressed. The last tarsal segments are also laterally compressed.

A recent study of the molecular phylogeny of the Family Platypezidae (Tkoč, Michal & Tothova, et al., 2016) found a difference in the position of the wings when at rest also differentiates Platypezinae. The wings of Melanderomyiinae and Callomyiinae overlap 50% to almost completely when at rest. The wings of Platypezinae are more outspread, overlapping 30% or less when at rest.

Sources

27, 30, 82.

Alfredo Colon
8/4/2022

Location: Albany, NY