Genus Liriomyza Mik 
Liriomyza Mik, 1894: 284. Type of 
genus: Liriomyza urophorina Mik, 
1894 (Europe) . 
In earlier literature (Hendel, 1931; 
Frick, 1952a; 1959) the concept of 
this genus appeared relatively simple, 
with the frons and scutellum yellow, 
the orbital setulae reclinate, and the 
costa extending to vein M 1+2. Study 
of much additional material in recent 
years, both in the Northern Hemisphere 
and also in Australia and New Zealand, 
has revealed a number of species 
correctly belonging in Liriomyza , in 
which either the frons or the scutellum 
is entirely black and the outer cross- 
vein is lacking. 
In most species, Liriomyza is readily 
recognizable, but a clear-cut segrega- 
tion from Calycomyza , Galiomyza , 
Metopomyza , and Phytolir iomyza has 
become virtually impossible on 
external charcters alone. The 
characteristic form of the aedeagus 
(figs. 625, 697), with the surstylus 
discrete and bearing one or two spines 
and sometimes a few weak hairs, is 
also distinctive. However, in a few 
species the distiphallus is greatly 
elongated (fig. 633), and there may be 
doubt about the generic position as 
between Liriomyza and Phytoliriomyza . 
The only consistent character for 
identifying Liriomyza is the presence 
of the stridulating mechanism in 
males, a structure that may sometimes 
be detectable only at a magnification 
of 400 X. This is similar to but not 
identical with that present in 
Agromyza (p. 57), with a "file” or 
line of scales along the center of the 
membrane connecting the abdominal 
tergites and sternites (fig. 621) and 
a "scraper" or ridge on the hindfemur 
(fig. 622). 
Liriomyza is a large genus, with over 
300 described species. It is the 
second largest genus in the Northern 
Hemisphere, but it is also well repre- 
sented in the Neotropical Region 
(Spencer, 1963a; 1973b), in Australia 
(Spencer, 1977d), and in New Zealand 
(Spencer, 1976b), where there has been 
a remarkable proliferation with 22 of 
the total 41 agromyzid species known 
there. In the United States, 80 
(including 1 unnamed sp.) described 
species are now recorded here, of 
which 11 are new (part 2, p. 288). In 
addition, five species are recorded as 
new to the United States: L. arctii , 
L. endiviae , L. lathyri , L. philadel - 
ph ivora , and L. taraxaci , of which L. 
endiviae is new to North America. 
Twenty-three other species are known 
in Canada (Spencer, 1969a; Sehgal, 
1971). Three new synonyms have been 
uncovered (part 2, p. 288). 
The majority of species are leaf 
miners, but one, L. angulicornis , 
forms stem mines. The type of the 
genus, L. urophorina , and some others 
known only in Europe, feed in seeds. 
Thirty-five species have been recorded 
as leaf miners in the United States, 
and the host of several others is 
known from Canada or can be deduced 
from the male genitalia, for example 
L. graminaceae , which certainly feeds 
on Poaceae. The favorite host family 
is Asteraceae, from which 16 species 
have been recorded, followed by 
Fabaceae, with 7 species. Other 
families in which hosts are known 
include Acanthaceae (1), Asclepiadaceae 
(2), Brassicaceae (1), Lamiaceae (1), 
Saxifragaceae (1), and Solanaceae (1). 
Some species are strictly host 
specific, such as L. asclepiadis on 
Asclepias and L. s tachyos on Stachys . 
The majority are oligophagous , feeding 
on one or more genera in the same 
family, but three are polyphagous, 
feeding on a number of unrelated 
families. These three, L. huido- 
brensis , L. sativae , and L. trifolii , 
are the most serious pests in the 
genus, attacking a wide range of 
cultivated crops (see here and also 
Spencer, 1973a). 
Although most species are restricted 
to the Dicotyledones , four — L. anguli- 
cornis , L. commelinae , L. marginalis , 
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