squama gray, margin and fringe black. 
Male genitalia. Aedeagus (figs. 285, 
286) with distiphallus symmetrically 
bowl shaped; sperm pump with unusually 
large blade. 
Host/early stages. Unknown. 
Holotype m. , Colorado, Boulder Co., 
Eldora, 3. VI. 61 (J. G. Chillcott), in 
CNC . 
Remarks. Although this species belongs 
to a group in which identification is 
difficult based on external characters, 
the aedeagus is of a form not known 
elsewhere in North America and is 
entirely distinctive. 
Ophiomyia fastosa (Spencer), new 
combination (new to U.S.A.) 
(Figs. 193-195) 
Melanagromyza fastosa Spencer, 1969a: 
67. Holotype male from Ontario in 
CNC. 
This species lacks the two primary 
generic characters of Ophiomyia — the 
male vibrissal fasciculus and the 
raised facial keel. It was described 
in Melanagromyza before the signifi- 
cance of the unusual form of male 
genitalia was appreciated. 
0. fastosa resembles 0. abutilivora , 
which has been confirmed as a true 
Ophiomyia feeding on Abut i Ion . A 
paratype from Alberta was caught on 
"wild mustard," and it is possible 
that the host will prove to be 
Brassica . 
Material seen. Colorado, Eagle Co., 
State Bridge, 7,000 ft, near Bond, 
24. VI-5. VII. 61 (B. H. Poole), in CNC. 
Ophiomyia frosti Spencer, new species 
(Figs. 187, 188) 
Head. Frons 1.5 times width of eye, 
not projecting above eye in profile; 
(orbital bristles all missing but as 
far as can be detected from basal pits 
2 ors, 3 ori), orbital setulae rec- 
linate; gena deepest in center below 
eye, 0.2 height of eye; vibrissa 
short, normal, peristomal hairs weak, 
sparse; 3d antennal segment round, 
without pubescence, arista appearing 
bare, bases of antennae narrowly sepa- 
rated by low facial keel. 
Mesonotum. (dc missing, no evidence 
of more than 2), acr sparse. 
Wing. Length in male 2.3 mm, C 
extending strongly to M 1+2, last 
section M 3+4 0.67 penultimate, outer 
crossvein more than own length from 
inner. 
Color. Black, mesonotum and abdomen 
distinctly shining; squama gray, 
margin and fringe black. 
Male genitalia. Aedeagus (figs. 187, 
188) asymmetrical, characteristic of 
genus; sternite IX with slightly 
extended hypandrial apodeme; sperm 
pump long, only slightly shorter than 
aedeagus. 
Host/early stages. Unknown. 
Holotype m. , New York, Tompkins Co., 
Ithaca, "16 May" (year not legible), 
(S. W. Frost), presented to USNM. 
Remarks. This species closely 
resembles 0. pulicaria (Meigen), which 
is common in Europe and is also known 
from Alberta and British Columbia 
(Spencer, 1969a: 93). The male 
genitalia, however, show the two to be 
distinct. (). pulicaria feeds on 
Taraxacum and related genera, forming 
a leaf mine along the midrib into the 
leaf blade, pupating at the base of 
the leaf. It seems probable that 0. 
frosti will feed in the same way. 
Ophiomyia lauta (Spencer), new 
combination 
(Figs. 181-183) 
Melanagromyza lauta Spencer, 1969a: 
70. Holotype male from Ontario in 
CNC. 
The fringe of numerous peristomal hairs 
255 
