backed, pronotum usually not visible from above, scutellum often extending backward over base of abdomen, and abdomen stalked and attached low on thorax.

This is a small group of rather uncommon insects, usually black, with interesting habits. Larvae are parasites of ant pupae; eggs are laid in large numbers on vegetation and the larvae on hatching attach themselves to a passing ant that carries them

to its nest, where the eucharitid larvae leave the ant and attack the ant pupae.

CHALCIDIDS Family Chalcididae Identification: Generally uniformly dark-colored. Hind femora greatly swollen, toothed beneath. Hind coxae considerably larger than front coxae, long and cylindrical. Ovipositor usually short. Wings not folded longitudinally at rest.

Chalcidids are mostly 2-7 mm., and are relatively common. Larvae are parasites of a variety of insects.

CHALCEDECTIDS Family Chalcedectidae Not illus.

Identification: Hind femora greatly swollen. Hind coxae little if any larger than front coxae.

Four rare species have been reported from the s. U.S. Larvae are parasites of Buprestidae.

LEUC O SPIDID S Family Leucospididae

Identification: Similar to Chalcididae but larger (8-12 mm.). Brightly colored with black and yellow. Somewhat humpbacked in appearance. Wings folded longitudinally at rest. Ovipositor curves upward and forward along dorsal side of abdomen.

These are a small group of uncommon insects resembling small yellowjackets. They are usually found on flowers. Larvae are parasites of various wasps and bees.

TORYMIDS Family Torymidae

Identification: Elongate, usually metallic green, and mostly 2-4 mm. Hind coxae much larger than front coxae. Ovipositor as long as body or longer. Hind femora slender, or if greatly swollen hind coxae are triangular in cross section. Parapsidal sutures present. Abdomen smooth, shiny.

Larvae of some species are parasites of various caterpillars, gall insects, or insect eggs; larvae of others feed on seeds.

ORMYRIDS Family Ormyridae Not illus.

Identification: Similar to Torymidae but parapsidal sutures indistinct or absent, ovipositor short and often hidden, and abdomen usually with rows of deep punctures.

This is a small group of rather rare chalcids. Larvae are parasites of gall insects.

FIG WASPS Family Agaonidae

Identification: Black. Head of 9 somewhat oblong, with a deep dorsal longitudinal groove. 9 winged, c? wingless. Front and hind legs stout, middle legs slender.

This group is represented in the U.S. by 2 species, 1 occurring

in Florida and 1 in California and Arizona. Fig wasps pollinate certain varieties of figs.

PTEROMALIDS Family Pteromalidae

Identification: Tarsi 5-segmented. Apical spur of front tibiae large and curved. Mesopleura slightly concave, or with a broad shallow groove. Front and hind coxae about same size. Hind femora not enlarged. Pronotum in dorsal view somewhat conical, narrowed toward front.

Pteromalids are common insects, and most of the chalcids encountered by the general collector will probably belong to this family. They are mostly 2-4 mm., and are usually black or metallic green. Larvae are parasites of a variety of insects, and many species are important agents in the control of crop pests.

EURYTOMIDS or SEED CHALCIDS Family Eurytomidae Identification: Similar to Pteromalidae but pronotum in dorsal view squarish, not particularly narrowed anteriorly. Usually dull black, not shiny. Thorax rough or pitted. Abdomen of $ rounded or oval. Often somewhat hairy.

Eurytomids are fairly common chalcids. Some larvae are parasites of other insects and some feed on plants; a few are parasites as young and plant feeders when older. Plant-feeding species attack seeds and stems or are gall makers.

PERILAMPIDS Family Perilampidae

Identification: Relatively large chalcids; most are 6-8 mm. and metallic blue or blue-black. Thorax stout, pitted with punctures. Pronotum in dorsal view transversely linear. Abdomen small, in profile triangular, shining. Perilampids strongly resemble cuckoo wasps (Chrysididae; p. 338), but have a differently shaped abdomen and a more reduced wing venation.

Larvae are mostly hyperparasites, attacking the Diptera and Hymenoptera that are parasitic in caterpillars.

Gall Wasps and Others: Superfamily Cynipoidea

Pronotum in lateral view (see p. 333) more or less triangular, extending to tegulae or nearly so. Antennae threadlike, 13- to 16-segmented. Trochanters usually 1-segmented. Ovipositor rises anterior to apex of abdomen. Wing venation reduced. (For additional characters see p. 319.) The most distinctive features of the Cynipoidea are the wing venation and the threadlike antennae.

Most members of this group are black and 2-8 mm.; many have the abdomen shiny and often laterally flattened. More than 800 species of Cynipoidea occur in the U.S. The vast majority are gall wasps (Cynipinae) and the rest, as far as known, are parasites of other insects.

IBALIIDS Family Ibaliidae

Identification: Usually black and yellowish brown, the abdomen banded. Length 7-16 mm.; abdomen elongate and laterally flattened. 1st segment of hind tarsi twice as long as other segments combined; 2nd segment with a long apical process extending to tip of 4th segment. FW usually with brownish spots in middle and at apex.

This is a small and rare group. Larvae are parasites of horn tails (Siricidae).

LIOPTERIDS Family Liopteridae Not illus.

Identification: Abdomen stalked and attached far above base of hind coxae. Propodeum with a median furrow.

Three rare species occur in Texas, Idaho, and California. Their larval stages are unknown.

FIGITIDS Family Figitidae

Identification: A small group of shining black insects, mostly 3-6 mm. Anacharitinae: abdomen distinctly stalked, attached near base of hind coxae. Aspiceratinae: 2nd abdominal tergum (1st tergum forms stalk, and 2nd is 1st tergum in swollen part of abdomen) somewhat shovel-shaped, in lateral view narrow dorsoventrally, shorter than 3rd along middorsal line. Figitinae: 2nd abdominal tergum not particularly shovel-shaped, wider dorsoventrally in side view, and about as long as 3rd along mid-dorsal line.

Figitids are not common. Larvae are parasites of pupae of various Diptera (Aspiceratinae and Figitinae) or lacewings (Anacharitinae).

CYNIPIDS Family Cynipidae Identification: Eucoilinae: 4-6 mm., shining black, scutellum with a dorsal O-shaped elevation. Charipinae (not illus.): 2 mm. or less; thorax smooth. Cynipinae: usually over 2 mm. (mostly 6-8 mm.), the thorax rather rough, the abdomen oval and shining.

Eucoilinae and Charipinae are parasitic in the larval stage, Eucoilinae on pupae of Diptera and Charipinae on the braconids that parasitize aphids. These cynipids are more common than the figitids.

The vast majority of Cynipoidea the general collector will encounter will be Cynipinae (gall wasps), many of which are common insects. They either are gall makers or live in galls formed by another organism; each gall maker forms a characteristic gall on a particular part of a particular plant. The galls are much more often seen, and are usually more distinctive, than the gall wasps themselves. Many gall wasps form galls on oak leaves.



Abdomen of Figitid

Hind tarsus of Ibaliid

Scutellum of Cynipid


Abdomen of Figitid


Abdomen of Figitid

Woolly oak galls made by Gall Wasp

GALL WASP (Cynipinae)


Superfamily Evanioidea

Abdomen attached high above hind coxae. Antennae threadlike, 13- or 14-segmented. Trochanters 2-segmented. Venation fairly complete. FW with a costal cell. (For additional characters see p. 319.)

ENSIGN WASPS Family Evaniidae

Identification: Black, somewhat spiderlike in appearance, and 6-10 mm.; the small abdomen is carried like a flag (hence the common name). Characteristic appearance: thorax stout, abdomen small and attached by a slender stalk high above hind coxae. Ovipositor very short, not protruding.

Larvae are parasitic in the egg capsules of cockroaches, and adults are likely to be found in places where cockroaches occur.

GASTERUPTIIDS Family Gasteruptiidae Identification: Similar to Ichneumonidae (p. 322) but head set out on a slender neck, abdomen attached high above hind coxae, antennae short, and FW with a costal cell, only 1 recurrent vein, and cubital vein complete. Ovipositor long, often as long as body. Black, 13-20 mm.

Adults are fairly common, and are usually found on flowers. Larvae are parasites of solitary wasps and bees.

AULACIDS Family Aulacidae

Identification: Similar to Gasteruptiidae but antennae longer and FW with 2 recurrent veins. Black, or black with a reddish abdomen, and wings often banded or spotted.

Aulacid larvae parasitize various wood-boring insects, and adults are generally found around logs in which the hosts occur. These insects are moderately common.

Superfamily Pelecinoidea

Female about 2 in., shining black, with wings short and abdomen very long and slender, cf about 1 in., abdomen club-shaped. (For additional characters, see p. 319.)

PELECINIDS Family Pelecinidae

Identification: By the characters of the superfamily.

This group is represented in the U.S. by a single species, Pelecinus polyturator (Drury), which occurs in the eastern part of the country. Females, which are very distinctive in appearance, are fairly common but males are very rare. Larvae are parasites of white grubs.

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