UNITED STATES DEPARTMENT OF AGRICULTURE 



DEPARTMENT BULLETIN No. 1363 



Washington, D. C. T February, 1926 



HOST RELATIONS OF COMPSILURA CONCINNATA MEIGEN, AN IMPORTANT 

 TACHINID PARASITE OF THE GIPSY MOTH AND THE BROWN-TAIL 

 MOTH 



By It. T. Webber, Assistant Entomologist, and J. V. Schaffneb, Jr., Principal 

 Scientific Aid, Gipsy Moth and Browne-Tail Moth Investigations, Bureau of 

 Entomology 1 



CONTENTS 



Page 



Source of collections and data __ 2 



Care of collections and methods of 



rearing 4 



Life history and hibernating hosts 4 



Status of hibernating hosts of Comp- 



silura 5 



Generations of Compsilura 7 



Page 



Status of summer hosts— 8 



Records of Compsilura rearings other 

 than those recorded at the Gipsy 



Moth Laboratory 27 



Effect upon native parasites 27 



Effect upon host species 30 



Literature cited 31 



The depredations wrought by the gipsy moth (Porthetria dispar 

 L.) and the brown-tail moth {Euproctis chrysorrhoea L.) in eastern 

 Massachusetts have been responsible for the introduction of many 

 European parasites into the United States. Among the imported 

 parasites which were successfully established is Compsilura concin- 

 nata Meigen, a tachinid fly common to the European countries where 

 the brown-tail moth is found and credited with a long and varied 

 host list. This parasite was first introduced into Massachusetts in 

 1906 and found to be generally distributed over considerable terri- 

 tory in 1909. A brief account of the life history, colonization, etc., 

 of this tachinid appeared in a bulletin by Howard and Fiske issued 

 by the Bureau of Entomology in 1911 (7), 2 and a much more elabor- 

 ate summary, detailing the life history, was published by Culver in 

 1919 (£). Tothill (£), in 1922, also published on the life history of 

 Compsilura. 



Since the establishment of a foreign insect in a new environment 

 may bring about some change either beneficial or detrimental to its 

 hosts and host affiliations, plans were made to study the effect of this 

 introduced parasite on native larvae. Accordingly, during the spring 



»The writers are indebted to the personnel of the Gipsy Moth Laboratory for their 

 assistance; to H. G. Dyar, of the TJ. S. National Museum, and the late F. H. Mosher, of 

 the Gipsy Moth Laboratory, for identification of the Lepidoptera ; and to C. F. W. Muese- 

 beck for determination of the Hymenoptera. 



2 Reference is made by number (italic) to " Literature cited," p., 31. 



56991—26 1 



