families are common; the Diapriinae are minute, with the venation greatly reduced (no closed cell in hind wing); the Belytinae are larger (5-7 mm.), with slightly more venation (a closed cell in hind wing).

SCELIONIDS Family Scelionidae Identification: Minute insects, usually 2 mm. or less; black (rarely brown). Antennae elbowed, rising low on face, generally 11- or 12-segmented (occasionally 7- or 8-segmented and clubbed, the club unsegmented). Abdomen flattened, the lateral margins sharp. Venation greatly reduced, chalcidlike. HW without a jugal lobe.

This is a large, fairly common group. Larvae are chiefly egg parasites. Some females, which parasitize the eggs of grasshoppers or mantids, attach to the abdomen of a grasshopper or mantid and ride around on it until it lays its eggs; then the scelionid gets off and oviposits in the eggs of the host.

PLATYGASTERIDS Family Platygasteridae

Identification: Similar to Scelionidae but antennae 9- or 10-segmented, if clubbed the club segmented. Abdomen more or less flattened, less so than in Scelionidae.

Platygasterids are minute insects, shining black, with almost no wing venation. Some species have a peculiarly shaped abdomen. Females of the genus Inostemma have a long handlelike process extending from the base of the abdomen forward over the thorax (this process serves as a receptacle for the long ovipositor when it is withdrawn into the body). Most larvae are parasites of gall gnats (Cecidomyiidae); some parasitize mealybugs or whiteflies.

Superfamily Bethyloidea

Pronotum in lateral view variable, sometimes triangular, sometimes quadrate. Antennae generally 10- to 13-segmented and threadlike. Trochanters 1-segmented (except Trigonalidae). Ovipositor issues from apex of abdomen. Venation usually reduced. HW of forms with reduced venation has a jugal lobe. Larvae, as far as known, parasites of other insects.

CUCKOO WASPS Family Chrysididae See also PI. 15

Identification: Body metallic blue or green, usually with coarse sculpturing. Abdomen with 4 or fewer segments, concave beneath, the last tergum often toothed apically. Hind wing with a distinct lobe at base and without closed cells.

Cuckoo wasps are about 6-12 mm. and have a brilliant metallic coloring; they are common insects. Some of them resemble perilampids (p. 330) and certain halictid bees (p. 356); they have more venation than a perilampid and not as much as a

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