 |
Saperda calcarata
Classification
Diagnostic Features of Larvae
- Larva. Large, robust; integument finely rugulose, clothed with coarse, castaneous hairs; labrum semicircular, widest at base, densely and coarsely haired; pronotum slightly wider than long, asperities very coarse, extending over three-fourths of length; eusternum coarsely haired, bearing a very few (about 20) asperities; sternellum having a very narrow band entirely across. Ampullae coarsely asperate; pleural tubercle bearing two strong setae and fine pubescence. Spiracles oval, peritreme strongly chitinized. Pupa. Form as in adult; head bearing stiff setae on inner margin of eyes, a transverse row at base of clypeus and about base of antennae; anterior median two-thirds of pronotum, scutellum mesonotum, and posterior median disc of metanotum bearing a few short, setiferous chitinous points, such points also occur on abdominal terga in a scattered transverse band more numerous at sides and increasing posteriorly, on lateral ventral parts of last segment very dense. Adapted from Craighead (1923).
Biology and Economic Importance
- The larva of this species is a very serious pest to Populus throughout the eastern US and Canada and west through the Rocky Mountain region. The eggs are laid in June and July on the trunks or larger branches of trees. They are inserted into the cambium in an irregular hole gnawed through the bark. For the first season the young larvae extend transverse galleries between the bark and wood which often entirely cut the cambium, killing the tree. During the second and third seasons large extensive mines are made in the heartwood, where pupation takes place. The trees are so honeycombed that great numbers of them break off in the wind. A knotty swelling is often caused at the point where the young larvae are feeding. Piles of frass several inches deep are noticed below infested trees. Adapted from Craighead (1923).
Selected References to Larvae Specimens
| |
