Immature Stages of Elasmidae
Immature stages of Elasmidae were discussed in detail by Clausen (1940), as follows:
The eggs of the Elasmidae are of simple form, either subcylindrical or kidney shaped in outline, the anterior end slightly the wider and both ends smoothly rounded. That of E. claripennis Cam. is stated to have a short peduncle at the narrower end, and in E. nudus Nees (Parker, 1924) the chorion is covered with minute tubercles.
The first‑instar larva is hymenopteriform, with the segmentation distinct and the body widest in the anterior abdominal region. That of E. hispidarum has a median row of fleshy pseudopodia ventrally, these being situated intersegmentally, the first between the second and third thoracic segments. In E. nudus (Fig. 52), the body is somewhat cylindrical and, like E. hispidarum, has spiracles on the second thoracic and the first three abdominal segments.
Please CLICK on picture to view details:
The second‑instar larva of E. hispidarum is similar to the first, as is also the third, except for the appearance of the nine pairs of spiracles, situated on the second and third thoracic and the first seven abdominal segments.
The mature larva, which is the fourth instar in E. hispidarum, bears a row of retractile intersegmental pseudopodia on the median line, both dorsally and ventrally. They are extruded only when the body is fully extended and presumably serve in locomotion within the host leaf mine. The spiracle number and arrangement in this species and in E. nudus (Fig. 52), also, are identical with those given above for the third instar.
The pupae of E. hispidarum and of an undetermined species reared from bagworms in Japan are distinguished by the extension of the scutellum into a distinct bifurcate process which in the latter species, extends over about one‑third of the length of the abdomen.