Like all insects, the body of the pine sawfly is divided into three sections (front to back): head, thorax, and abdomen. Each section consists of several segments. For the purposes of this resource, it is sufficient to know that the thorax consists of three segments and the abdomen ten (with vestiges of an eleventh). In adult pine sawflies, the thorax bears the locomotory appendages: two pairs of wings and three pairs of legs. In addition to the six legs, larval pine sawflies have abdominal appendages called prolegs that serve in walking.
The images shown here present anatomical features that are relevant for identification of pine sawflies to species. Note that the ends of the antennae are broken in the male specimen pictured below.
Pinning pine sawfly specimens (see instructions here) is very helpful for not only preserving these long-term, but for viewing the features which can be used for identification. Dissection is usually needed to view the female gonapophyses VIII ("lancets"), and always to view the male penial scleritespenial sclerite:
paired sclerites of the male genitalia that convey spermatozoa into the female genital tract (Boudinot 2018). In Diprion, these presumably also help anchor the male in place during mating. Penial sclerites in Diprion have a hatchet-like shape, with the valvura being the 'haft' and the valviceps the 'head'.
. To dissect, specimens will need to be fresh or preserved in ethanol (>90% for long-term storage); dry specimens can be relaxed for dissection by placing them in an enclosed container with listerine-moistened paper towels.
Author: Z. Griebenow
Content last updated January 2026
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