1937] 
Megamorphic and Mimetic Flies 
121 
elongate. Last two joints about as long as first, not set on a 
pedicel. Third joint one and three-fourths times length of 
second. Second about equal width of front at narrowest 
point. Pile of head and face everywhere black, vertical pile 
and that of upper front converging to come together just 
above ocelli. Pile of upper face exceedingly appressed, black, 
bristly, the face punctate, developed on the lower face into a 
black beard of long bristles above oral margin. 
Dorsum of thorax shining black, covered thickly with very 
short appressed bristles, a few golden ones on the sutures. 
Pleurae similar but with longer bristly pile. Scutellum de- 
veloped into a pair of enormous black spines, deeply sulcate 
in the middle, and black bristly or pilose to their apices. 
Spines held at a forty-five degree angle. 
Abdomen shining black, a deep excavation on the apical 
lateral half of the third and again on the fourth segments. 
Apical half of second segment long, golden pilose, a similar 
annulus or transverse band across the middle of the fourth 
segment so that the first excavation lies between and is 
black. Remainder of abdomen, except for a little more black 
following the second golden band, is deep bright orange 
reddish pilose. 
Legs everywhere dark shining black, black bristly, the 
hind metatarsi (and the following ones to a less extent) 
enormously flattened and broadened, but not markedly thick. 
Wings with basal half or three-fifths black, (very dark 
brown) the remainder except for light brown tip, yellow with 
yellow veins. 
Length 25 mm. 
South America, without further data. Type in the 
Carnegie Museum. 
Curiously, this fly forms part of a three-part mimetic 
complex, the others being an Asilid fly and a bee from the 
same region. 
