Factors affecting success of galls of Aditrochus coihuensis (Hymenoptera: Pteromalidae)
Author
Summary, in English
Galls of Aditrochus coihuensis (Hymenoptera:
Pteromalidae) were collected from their host tree, the southern beech
Nothofagus dombeyi, near San Carlos de Bariloche, Argentina, during the
spring of 2007. Galls were carefully examined and classified as successful
or unsuccessful based on insect remains and emergence-hole diameter.
Gall properties (diameter, wall thickness, chamber diameter, wall
toughness) were measured and compared between successful galls and
unsuccessful (parasitized) galls. Gall diameter and wall thickness were
strongly correlated and thick walls seem to function as a protection against
parasitoids. Parasitoids (Torymidae) that were found within some galls had
an ovipositor length shorter than wall thickness of fully developed galls.
Most likely, parasitoids attack galls only during a limited time when the wall
338 Rev. Soc. Entomol. Argent. 70 (3-4): 337-34, 2011
is thin enough. Wall toughness did not seem to influence gall success. In
total 67% of the galls suffered from parasitoids. Inquilines (Curculionidae)
were found within some gall walls, with preference for larger galls and for
those with thicker walls. Traces of potential bird or wasp predation were
also found in a few specimens. Our present findings contribute original
descriptive information on these galls. Overall, our results lend further
support on the potential importance of natural enemies on gall evolution.
Pteromalidae) were collected from their host tree, the southern beech
Nothofagus dombeyi, near San Carlos de Bariloche, Argentina, during the
spring of 2007. Galls were carefully examined and classified as successful
or unsuccessful based on insect remains and emergence-hole diameter.
Gall properties (diameter, wall thickness, chamber diameter, wall
toughness) were measured and compared between successful galls and
unsuccessful (parasitized) galls. Gall diameter and wall thickness were
strongly correlated and thick walls seem to function as a protection against
parasitoids. Parasitoids (Torymidae) that were found within some galls had
an ovipositor length shorter than wall thickness of fully developed galls.
Most likely, parasitoids attack galls only during a limited time when the wall
338 Rev. Soc. Entomol. Argent. 70 (3-4): 337-34, 2011
is thin enough. Wall toughness did not seem to influence gall success. In
total 67% of the galls suffered from parasitoids. Inquilines (Curculionidae)
were found within some gall walls, with preference for larger galls and for
those with thicker walls. Traces of potential bird or wasp predation were
also found in a few specimens. Our present findings contribute original
descriptive information on these galls. Overall, our results lend further
support on the potential importance of natural enemies on gall evolution.
Department/s
Publishing year
2011
Language
English
Pages
337-346
Publication/Series
Revista de la Sociedad Entomológica Argentina
Volume
70
Issue
3-4
Links
Document type
Journal article
Publisher
Sociedad Entomologica Argentina
Topic
- Zoology
Keywords
- Nothofagus dombeyi
- Cohiue
- Patagonia
- Galling insects
Status
Published
Project
- Chemical ecology of social insects
Research group
- Pheromone Group
ISBN/ISSN/Other
- ISSN: 0373-5680