Agriculture Reference
In-Depth Information
often, a caudal appendage (which may function
as an egg-tooth, helping the first-instar larva to
break out of the egg); early and later instars
often very different in form; pupation usually
occurs in a silken, often iridescent, cocoon. Most
species are parasitoids of Lepidoptera but some
attack Coleoptera.
EXAMPLES:
Diadegma fenestralis, Glypta
spp.,
Ichneumon
spp.,
Itoplectis
spp.,
Lissonota
spp.,
Ophion luteus
(yellow ophion),
Pimpla
hypochondriaca
(red-legged ichneumon),
Scambus pomorum
(apple blossom weevil
parasitoid).
scale insects), Diptera and Lepidoptera, espe-
cially lepidopterous eggs and larvae.
The main families of economic importance are
as follows.
11. Family TORYMIDAE
Often brilliantly metallic-green, elongate-bodied
chalcids with a very long ovipositor; hind coxae
enlarged; hind femora sometimes toothed; tarsi
5-segmented. Mainly parasitoids of gall-forming
insects, but family also includes some phyto-
phagous species.
EXAMPLES:
Megastigmus
spp. (seed wasps),
Torymus bedeguaris
(a parasitoid in bedeguar
galls on rose).
9. Family BRACONIDAE (braconids)
Adults up to 15 mm long and forewing cross-vein
2m-cu absent
(Fig. 154b).
Larvae similar to
those of ichneumonids, pupating within the host
or externally in silken cocoons; they attack
mainly Lepidoptera but also many other insects,
including dipterous leaf miners.
EXAMPLES:
Apanteles
spp.,
Bracon
spp.,
Dacnusa
spp.,
Macrocentrus
spp.,
Meteorus
spp.,
Microctonus
spp.,
Microgaster
spp.,
Perilitus
spp.
12. Family EURYTOMIDAE
Pronotum broad and quadrate; hind coxae not
enlarged; hind femora untoothed. An exceed-
ingly variable family, including parasitic and
phytophagous species.
EXAMPLE:
Eurytoma
orchidearum
(orchid
wasp).
13. Family PTEROMALIDAE
10. Family APHIDIIDAE
Extremely variable chalcids, often metallic-
coloured with the gaster often more or less trian-
gular in profile (Fig.
155);
pronotum narrow;
hind coxae not enlarged; hind femora untoothed;
tarsi 5-segmented; wings without hair fringes, the
venation characteristic
(Fig. 156a).
Includes
parasitoids of many insect groups, including vari-
ous crop pests.
EXAMPLES:
Pteromalus puparum
(large white
butterfly parasitoid),
Trichomalus perfectus
(cabbage seed weevil parasitoid).
Parasitoids of aphids (often included within the
family Braconidae).
EXAMPLES:
Aphidius
spp.,
Diaeretiella rapae
(cabbage aphid parasitoid),
Ephedras
spp.,
Praon
spp.
Superfamily CHALCIDOIDEA (chalcids)
Antennae geniculate, with one to three annuli
(cf. superfamily Proctotrupoidea) and fewer
than 14 segments; wings, when present, without a
pterostigma and the venation much reduced;
pronotum not extending back to the tegulae (cf.
superfamily Proctotrupoidea). This superfamily
contains the largest number of species, most of
small size, and includes the smallest of all insects;
most are parasitoids or hyperparasitoids, the
former attacking mainly Hemiptera (notably
14. Family ENCYRTIDAE
A distinct group of chalcids, characterized by the
much enlarged spur on each mid tibia (Fig.
157);
forewing venation entirely separated from the
wing margin
(Fig. 156b).
Most are parasitoids of
