second in the leafminer. C. laricinellae was reported ineffective against the case- 
bearer because it acted as a secondary parasite, attacking the more effective A gathis 
pumila (327). Recent studies indicate it can be effective, especiaily in concert with 
A. pumila, as a successful multiple parasite. The species has been transferred to the 
Northwest where it 1s established on the larch casebearer (/047). 
F-519579 
Figure 198.—Adult of the parasite Chrysocharis 
laricinellae. 
Dahlbominus fuscipennis (Zetterstedt), a parasite of several species of sawflies in 
Europe, was introduced to Canada in 1934 for release against the European spruce 
sawfly. The following year, shipments were received from Canada for release 
against the same species in Maine. Since then, releases have been made against 
several other sawflies in Canada and the United States. So far, it has been recovered 
in this country from the European spruce sawfly in New England, the European 
pine sawfly in New Jersey, the redheaded pine sawfly in Michigan, the Virginia 
pine sawfly in Virginia, Neodiprion pratti paradoxicus Ross and N. pinusrigidae 
(Norton) in New Jersey, the red pine sawfly and the introduced pine sawfly in 
Wisconsin and North Carolina, the balsam fir sawfly in Maine, Gilpinia frutetorum 
(F.) in Connecticut, and others (328, 697). 
Adults are 2.3 to 2.8 mm long. The head, thorax, and abdomen are black; the 
wings have a smoky tinge; the legs are white to light brown, except the femur which 
is black; and the antennae are elbowed and black, except for a white scape in the 
female. This species is an external parasite of sawfly larvae and of pupae within 
their cocoons. There are from two to seven generations per year, depending on 
location. It has never become a very effective parasite of the spruce sawfly. Yet, 
almost 50 percent parasitization of the European pine sawfly has been recorded 
locally in New Jersey. 
The genus Jetrastichus contains a large number of parasites of important forest 
insect pests. Descriptions of most North American species and information on their 
distribution and hosts have been published (/5, /75). 
Tetrastichus turionum (Hartig) was imported from Europe during the 1930’s and 
released in New England, New York, and New Jersey against the European pine 
shoot moth. Several years later it was also released in Ontario. It occurs in 
Massachusetts, New Jersey, Connecticut, on Long Island, N.Y., and in southern 
Ontario. The adult is a tiny, iridescent, blue-green insect. The antennae are brown 
and the apices of the femora and the tarsi are light yellow or white. This is a pupal 
parasite and it has one generation per year. So far, it has been of no consequence in 
suppression of the shoot moth in this country. 
417 
