Genus Metopomyza Enderlein 
Metopomyza Enderlein, 1936: 180. Type 
of genus: Agromyza flavonotata Hali- 
day, 1831 (Europe). 
This small genus of only 12 known 
species resembles Liriomyza in having 
the scutellum yellow, but all species 
are otherwise darker, with the head 
black, brown, or at palest ochreous, 
and the legs are generally black, with 
at most the knees yellow. The 
s tridulating mechanism in Liriomyza is 
lacking here. 
When revising European species, 
Spencer (1976a) noted that the male 
terminalia, particularly the arrange- 
ment of characteristic bristles within 
the epandrium (figs. 1027, 1031), 
indicate closer relationship with 
Phytoliriomyza than with Liriomyza . 
Three species are known in the United 
States, of which one is holarctic and 
one is known only in California and 
Washington. Metopomyza scutellata has 
been reared from Carex in Europe and 
the two other American species 
probably have hosts in the same genus 
or in the Poaceae. 
Key to Metopomyza 1. Legs entirely black M. nigripes Spencer 
Species Synopsis. Frons dark, brownish black, orbit weakly 
shinies > 1 reclinate ors, 3 more slender incurved 
ori; gena dark brown, 0.33 height of eye (fig. 
1023); antenna entirely black; mesonotum with 2+1 
or 3+1 dc, brilliantly shining black; pleura large- 
ly black, only notopleuron slightly paler, brownish; 
scutellum lemon yellow centrally, black at sides; 
squama gray, margin and fringe black; halter white; 
wing length in female 1.6—1.75 mm, last section of 
M 3+4 twice length of penultimate; male genitalia 
unknown. 
Host/Early Stages. Unknown. 
Distribution. California, Washington. 
Reference. Spencer, 1981: 335. 
Femora with yellow knees 2 
2 (1). Discal cell large, last section of vein M 3+4 only 
twice length of penultimate (fig. 1024) 
7 M. inter frontal is (Melander) 
Synopsis. Small black species, wing length 1.7-2. 3 
mm; frons centrally ochreous yellow, orbit promi- 
nent, darker; antenna black, with 3 or 4 postsutural 
dc; scutellum lemon yellow; side of thorax black; 
legs black apart from yellow knees; squama yellow, 
margin and fringe black; wing base and halter yel- 
low; male genitalia with aedeagus as in figures 
1025, 1026; surstylus angular, fringed with strong 
hairs or weak bristles (fig. 1027, A), hindcorner of 
epandrium with group of short, stout bristles and 
further row of bristles along lower margin (fig. 
1027, B). 
Host/Early Stages. Unknown but presumably either 
Cyperaceae or Poaceae. 
Distribution. Northern California, Illinois, Kansas, 
Michigan, Texas, Virginia, Washington; widespread in 
Canada; Europe. 
References. Frick, 1959: 412; Spencer, 1969a: 198; 
1981: 333. 
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