Agriculture Reference
In-Depth Information
Fig.
261 Puparium of
Phytomyza syngenesiae:
(a) lateral view; (b) dorsal view (xl5).
Fig. 262
Adult of
Phytomyza hordeola
(x20).
rest of mouthparts, and each with two prominent
teeth;
posterior spiracles
each with 8-10 pores
(cf. American serpentine leaf miner,
Liriomyza
trifolii,
p. 189).
Puparium
3 mm long, yellow-
ish-brown to dark brown, slightly flattened
(Fig.
261).
mines in the leaves of various weeds and orna-
mental plants, and in certain field crops such as
flax, linseed and pea
(Plate 8e);
mines may occur
on either the upper or the lower side of leaves. In
common with
P. syngenesiae,
pupation takes
place at the end of the larval mine, but the
puparium is formed immediately below the epi-
dermis on the same side of the leaf as the rest of
the mine. Larvae of this species are similar in
appearance to those of
P. syngenesiae.
Phytomyza fuscula
Zetterstedt
This species is essentially similar to
Phytomyza
nigra
(p. 191) but is absent from the British Isles.
In continental Europe, it is a minor pest of ce-
reals, especially in more northerly areas; in
Germany, important attacks on false oat are re-
ported.
Phytomza fuscula
is best distinguished
from
P. nigra
by examining the anterior spiracles
of larvae or puparia, those of
P. fuscula
(each with eight pores) being borne on a pair of
short, broad stalks arranged in the form of a
prominent V.
Phytomyza ramosa
Hendel
Teasel fly
9
This widespread, relatively large species is asso-
ciated with
Dipsacus
and, less frequently, other
members of the Dipsacaceae. The white larva
forms an elongate mine confined mainly to the
mid-rib of a leaf, but (at least on small leaves)
with short lateral galleries extending into the leaf
lamina; mines may also extend into the main
stem. Pupation occurs within the main gallery in
a whitish puparium (3.5 mm long). Adults are
mainly black (wing length: 2.2-3.2mm). Al-
Phytomyza hordeola
Goureau
larva =
A chrysanthemum leaf miner
Adults of this widely distributed and generally
common leaf miner
(Fig. 262)
are similar in ap-
pearance to those of
Phytomyza syngenesiae
(p.
192) and, mistakenly, both species have been re-
ferred to in older literature as
'P. atricornis\
The
larvae are very polyphagous and form whitish
9
The name "teasel fly' is most frequently applied by
commercial teasel growers to the pest
Endothenia
gentianaeana,
a small moth (family Tortricidae) whose
larvae damage the seed heads of teasel and cause them
to disintegrate (see p. 220).