Biology Reference
In-Depth Information
447
Liriomyza trifolii (Burgess) ( 447-449 )
larva
American serpentine leaf miner
A mainly North American species but frequently
introduced into Europe on Chrysanthemum cuttings
imported from America, the Canary Islands, Kenya and
Malta; now established in greenhouses or outdoors in
various parts of mainland Europe. In addition to
chrysanthemum, infestations also occur on many other
hosts, including vegetable crops. This insect is a
notifiable pest in several European countries.
=
DESCRIPTION
Adult: wings 1.2-1.5 mm long; greyish black, with a
mainly yellow head and a bright yellow scutellum;
antennae bright yellow; legs with yellow coxae and
femora, and brown tibiae and tarsi; costa reaching vein
M1
447 Fully-fed larva of American serpentine leaf miner
( Liriomyza trifolii ).
2, short of apex of wing (cf. Chromatomyia
syngenesiae , p. 198). Egg: 0.2
+
448
0.1 mm; oval, smooth
and translucent. Larva: up to 2 mm long; yellowish
orange; posterior spiracles with three pores, the outer
ones elongate. Puparium: 1.5 mm long; yellowish
brown.
×
LIFE HISTORY
Eggs are deposited singly in the leaves of host plants,
each female being capable of depositing several
hundred over a period of about a month. Eggs hatch
within a few days. The larvae then mine the leaves, each
forming a contorted, whitish gallery which contains a
meandering double line of dark frass along its length;
fully fed larvae vacate the mines about 10-14 days later
and pupate in the soil (cf. Chromatomyia syngenesiae ,
p. 198). Adults emerge a week or two later. Breeding is
continuous under favourable conditions, the lifecycle
being greatly shortened by high temperatures (but
protracted by low temperatures and poor lighting
conditions), and populations build up rapidly following
an original infestation. Once established, infestations
may also spread to outdoor plants, including common
weeds such as bittersweet ( Solanum dulcamara ),
common ragwort ( Senecio jacobaea ) and groundsel
( Senecio vulgaris ). In most instances, populations in
northern Europe are unlikely to survive the winter
outdoors.
448 Mines of American serpentine leaf miner ( Liriomyza
trifolii ) on Chrysanthemum .
449
DAMAGE
Leaves are disfigured by small, rounded adult feeding
punctures (cf. those of Chromatomyia syngenesiae ,
p. 198); the leaf mines, when numerous, cause
considerable damage to the foliage, checking growth
and affecting crop quality and marketability.
449 Adult feeding punctures of American serpentine leaf
miner ( Liriomyza trifolii ) in leaf of Chrysanthemum .
Search WWH ::




Custom Search