LIBRARY

DIPTERA 731
FOSSIL RECORDS
The first true fossils of DIPTERA appear in the Upper Lias (Triassic) of
Europe and consist of members of the archaic family ARCHITIPULIDJE
Tillyard 1933 of England and the recent families RHYPHIDlE Macquart
1838, of Australia, and the cosmopolitan BIBIONIDlE. In the Tertiary the
higher families, including the SYRPHlDlE, CULICID1E, TACHINID1E. and
others, appear and become abundant in the Oligocene. The most recent families
are the parasitic ORSTRIDJE and HIPPOBOSCIDJE.
IMPORTANT EXTERNAL ANATOMICAL CHARACTERS
Adults Larva? or Maggots
Size - minute to medium; 0.5-50.0 nun. Size - minute to large; 2-50 mm. long
long; wing expanse 1-100 mm.
Shape - relatively short, slender, or wide; Shape - dipteroid, vermiform, o[ spinsomewhat
flattened or cylindrical; a few dIe-shaped.
nearly globular.
Integument - thin, parchment-like, elas- Integument - thick, tough, elastic, or
tic, or delicate; a few tough and leathery, very delicate and easily ruptured.
Vestiture - mostly sparsely clothed with Vestiture - usually naked; setre, spines,
setre, spines, and hairs; some with scales and hairs may be present.
on bodies and wings.
Color - varied; dull and somber, or bright; Color - transparent, white, yellowish, or
many metallic. Wings often pigmented, pigmented brown, black, and other
colored or spotted (pictured). somber colors.
Head - hypognathous or nearly so: free, Head - very greatly reduced or rarely
with small neck. well developed in lower forms.
Eyes - large, often occupying much of Eyes - absent or present in certain
the head; holoptic in some males: fre- NEMATOCERA.
quently translucent red in color; rarely
divided.
Ocelli - three - arranged in amaH tri- Ocelli - absent.
angle on frons; absent in many families.
Antennre - exceedingly varied; simple or Antennal- usually inconspicuous; onecomplex:
usually two basal plus six-16 to six-segmented in free-living ionns
or up to 39 segments in simple type or or mere papillre in sedentary forms.
three or more segments in complex
type; latter with apical segment enlarged
and with a simple or segmented,
plain or ornamented arista; whorls of
hairs or other ornaments may be present.