The Biology of Leschenaultia Exul Townsend, a Tachinid Parasite of Malacosoma Americana Fabricius and Malacosoma Disstria Hubner1

1936 ◽  
Vol 29 (4) ◽  
pp. 593-613 ◽  
Author(s):  
Henry A. Bess
1995 ◽  
Vol 127 (6) ◽  
pp. 877-893 ◽  
Author(s):  
Dylan Parry

AbstractLarval and pupal parasitoids were studied from collections made in endemic, outbreak, and post-outbreak populations of forest tent caterpillar (FTC), Malacosoma disstria, at 21 sites in Alberta, Canada, from 1989 to 1994. The parasitoid complex included 18 identified species. Aleiodes malacosomatos (Mason) (Hymenoptera: Braconidae) was common in low density populations and was the only species to attack FTC larvae prior to the fourth instar. Leschenaultia exul (Townsend) (Diptera: Tachinidae) was the most abundant larval parasitoid in endemic populations and after the 2nd year of outbreak. Although prevalent early in outbreaks, Patelloa pachypyga (Aldrich and Webber) (Diptera: Tachinidae) declined in older outbreaks possibly because it completes larval development later than other tachinids, leaving it vulnerable to competition from aggressive pupal parasitoids. I hypothesize that early initiation of oviposition allows L. exul to be more successful than P. pachypyga in low density populations because caterpillars have dispersed before the latter species initiates oviposition. I recorded lower pupal parasitism by Arachnidomyia aldrichi (Parker) (Diptera: Sarcophagidae) in Alberta than has been recorded in other regions, although it was still the most abundant parasitoid reared in this study. Parasitism by A. aldrichi was significantly higher in cocoons collected from undergrowth vegetation than from the forest canopy. Other pupal parasitoids contributed relatively little to FTC mortality.


Author(s):  
H.M. Mazzone ◽  
W.F. Engler ◽  
R. Zerillo ◽  
G.F. Bahr

The nucleopolyhedrosis virus (NPV) of the forest tent cater - pillar (Malacosoma disstria Hubner) has been analyzed in our laboratories. As a representative of the Baculovirus class, the NPV has virus particles enclosed with in a proteinaceous structure, the inclusion body.


2003 ◽  
Vol 135 (3) ◽  
pp. 359-378 ◽  
Author(s):  
Melanie J. Filotas ◽  
Ann E. Hajek ◽  
Richard A. Humber

AbstractFuria gastropachaecomb. nov. (= Furia crustosa MacLeod et Tyrrell) has long been associated with declines in populations of the forest tent caterpillar, Malacosoma disstria Hübner; however, its prevalence and impact on host populations have never been documented. We clarify the nomenclature for this species, which has previously been called F. crustosa, and describe the morphology of F. gastropachae isolates from Maryland and New York. Epizootics of F. gastropachae were studied in M. disstria populations in New York and Maryland, United States of America. Prevalence (mean ± SE) of F. gastropachae in late fifth instar larvae in New York was 25.6 ± 7.8% compared with 22.2 ± 11.3% infection by virus and 23.3 ± 8.4% parasitism. In Maryland, F. gastropachae was not found in early instars and its incidence in fourth and fifth instars was 14.5 ± 7.3 and 21.6 ± 17.6%, respectively. Dipteran parasitoids were also important natural enemies with 38.3 ± 3.0 and 17.9 ± 1.4% parasitism in fourth and fifth instars, respectively. Virus was found in fewer than 5% of larvae collected. Furia gastropachae showed a marked tendency toward resting spore production in infected larvae, with 100% of larvae collected in New York and >80% of larvae collected in Maryland producing resting spores, either alone or in combination with conidia. The appearance of cadavers of larvae dying from fungal and viral infections was similar. Of 13 species of Lepidoptera exposed to F. gastropachae conidia in host-range bioassays, only 3.3% of Danaus plexippus (L.) (Lepidoptera: Danaidae), 5.6% of Pieris rapae (L.) (Lepidoptera: Pieridae), and 3.7% of Manduca sexta (L.) (Lepidoptera: Sphingidae) were successfully infected by this fungus.


1953 ◽  
Vol 85 (8) ◽  
pp. 297-310 ◽  
Author(s):  
C. R. Sullivan ◽  
W. G. Wellington

The forest tent caterpillar, Malacosoma disstria Hbn., and the eastern and western tent caterpillars, M. americanum (Fab.) and M. pluviale (Dyar), are common pests of several species of deciduous trees in Canada. All are colonial during the larval stage, but M. disstria differs from the others in one respect: it does not construct a communal tent. This difference in habit merits special consideration in any comparative study of larval behaviour, particularly in one concerned with the effects of physical factors upon the insects, since a tent modifies the effects of the physical environment considerably. Recently, a series of such studies was carried out, and one part of the work consisted of laboratory and field observations on the light reactions of larvae. The results obtained have raised a number of new questions which unfortunately cannot be answered now, hecause two of the species have been difficult to obtain in quantity since 1950. Nevertheless, the findings are presented here without additional delay, since they are of general interest, and other workers may wish to use them.


1993 ◽  
Vol 71 (8) ◽  
pp. 1511-1515 ◽  
Author(s):  
T. D. Fitzgerald ◽  
F. X. Webster

Behavioral assays show that the steroid 5β-cholestan-3-one, isolated from the abdomen of the larva of the forest tent caterpillar (Malacosoma disstria), constitutes the chemical basis of trail following in this insect. Caterpillars follow artificial trails prepared from solvent dilutions of the compound at rates as low as 10−11 g∙mm−11 of trail, though the true threshold sensitivity is likely to be one or two orders of magnitude lower than this. Fourth-instar caterpillars store an average of 58 ng of the pheromone. Field and laboratory studies indicate that the compound is fully competitive with their authentic trails. The caterpillars are highly sensitive to differences in the concentration of the pheromone, preferring stronger trails to weaker trails. The caterpillars also respond to 5β-cholestane-3,24-dione, a chemical not found in M. disstria but known to be a component of the trail pheromone of the eastern tent caterpillar, Malacosoma americanum.


Sign in / Sign up

Export Citation Format

Share Document