Insects - Pests of Ornamental Trees, Shrubs and Flowers - page 182

Eumerus tuberculatus Rondani ( 419-422 )
A small narcissus fly
A generally common pest of Narcissus bulbs but usually
confining its attacks to bulbs that are mechanically
damaged or diseased - e.g. infected with basal rot
( Fusarium oxysporum f. sp. narcissi ). Holarctic. Present
throughout Europe.

two long and two short, fleshy papillae. Puparium:
6-7 mm long; yellowish white.

LIFE HISTORY
Adults appear in the early spring, and deposit batches of
eggs in association with unhealthy narcissus bulbs.
Larvae emerge a few days later; they then enter the
bulbs to feed on the inner tissue in groups of five or six
but often in much larger numbers. Pupation takes place
in or around the neck of the host bulb in June or early
July. Adults emerge about two weeks later. Larvae of a
second generation become fully fed by the autumn.
They vacate the remains of the bulb, overwinter in the
soil and then pupate.

DESCRIPTION
Adult: 5-6 mm long; robust-bodied and mainly black;
head and thorax with a golden sheen, the thorax also
with a pair of whitish longitudinal lines; abdomen with
three pairs of white, crescent-shaped marks, and with
golden hairs along the sides and towards the tip;
pterostigma of fore wings dark brown or blackish; hind
femora (particularly of male) with a basal projection.
Egg: 0.7 mm long; white, elongate-oval and tapered at
one end. Larva: up to 9 mm long; whitish grey to pale
yellowish white, with an elongate reddish-brown
spiracular cone at the hind end, that protrudes beyond

DAMAGE
Narcissus bulbs are often totally destroyed by the
larvae. However, attacks rarely occur on healthy stock
and are, therefore, of secondary importance.

419

420

419 Small narcissus fly ( Eumerus tuberculatus ). 420 Larvae of small narcissus fly ( Eumerus tuberculatus ).

421

422

421 Puparium of small narcissus fly ( Eumerus tuberculatus ). 422 Small narcissus fly ( Eumerus tuberculatus ) damage to

bulb of Narcissus .