Immature Stages of Chrysididae
Immature stages of Chrysididae were discussed in detail by Clausen (1940), as follows:
The eggs of only a few species of Chrysididae were described as of 1940 (Clausen 1940). That of C shanghaiensis is 2.1 to 2.5 mm. in length, ca. 1/5th as wide, cylindrical, and slightly curved. There is a minute protuberance at the anterior end, and the chorion is finely roughened. In other species, the anterior end is slightly wider, and no protuberance at that end was mentioned in the descriptions.
Five larval instars have been detected in the few species upon which close observations of larval development have been made. The first-instar larva of C. shanghaiensis (Fig. 134), which is quite typical of the family, has 13 distinct body segments, with a relatively large, quadrangular head and simple mandibles. The caudal segment of the body is bifurcate. Integumentary spines and setae are lacking. The nine pairs of spiracles are situated on the 2nd thoracic and 1st 8 abdominal segments. In C. pacifica and C. dichroa, each body segment bears a ring of rather heavy spines. The caudal segment of Pseudochrysis neglecta, as described by Maneval, is more highly developed than in other species; and each lobe bears three rings of setae, and the tip is heavily sclerotized. Ventrally and dorsally at the base of each lobe is a fleshy spine or protuberance. The two lobes are curved inward and can be employed, forceps-like, for locomotion and combat.
The intermediate-instar larvae are similar in form and may be distinguished from the first by the more robust body, the absence of great reduction of the bifurcate caudal process after the first molt, the greater number of spiracles, and the dentate mandibles. In C. shanghaiensis, the 10th pair of spiracles, on the metathorax, appears on the 2nd instar larva, and their number and arrangement then persist unchanged until maturity. The mandibles are tridentate in the 2nd to 5th instars. These characters of the mature larva appear to be uniform for the family.
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