Revista Chilena de Historia Natural 85 (1): 113-122, 2012
RESEARCH ARTICLE
Mortality of the outbreak defoliator Ormiscodes amphimone
(Lepidoptera: Saturniidae) caused by natural enemies in northwestern Patagonia, Argentina
Outbreaks of the defoliator moth Ormiscodes amphimone are
occurring more frequently in numerous Nothofagus forests of Patagonia. However, little is known about the life
history of this species including its natural enemies as mortality agents. In this work we quantified mortality by
parasitoids and generalist predators at the egg, larval and pupal life stages of O. amphimone in a
Nothofagus pumilio (Poepp. & Endl.) Krasser forest in northwestern Patagonia. Parasitism of
eggs was relatively low (ca. 11 %), and we did not record significant larval predation by insectivorous birds.
However, we recorded elevated mortality caused by larval parasitoids (ca. 50 % in third instar larvae) and pupal
predators (ca. 75 %), which suggests that these natural enemies could play a significant role in regulating O.
amphimone populations. Our research is an initial step towards understanding the influence of natural enemies on
O. amphimone population dynamics.
Key words:
entomopathogenic nematode, Hyposoter, Nothofagus, parasitoids,
predation
