• Korean journal of applied entomology
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• v.48 no.4
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• pp.553-556
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• 2009

We surveyed natural enemies of Pachynematus itoi Okutani, newly recorded sawfly pest of Larix leptolepis, and investigated their occurrence and life cycle at Cheolwon and Taebaek, Gangwon Province in 2006~2007. Endasys liaoningensis was identified as main natural enemy of P. itoi Okutani. Parasitism of E. liaoningensiswas was 42%. Emergence period of E. liaoningensis was from May to September, and the peak of emergence was from 21th May to 20th June. It was suggested that the occurrence number and period of E. liaoningensis were quite closely relative to those of host, P. itoi.

• Korean journal of applied entomology
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• v.49 no.1
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• pp.17-22
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• 2010

Pachynematus itoi Okutani emerges three times a year, and overwinters as a pre-pupa in cocoon. First emergence of P. itoi was from 7th May to third June. Second and third emergence was from 20th June to 13th July and fourth to 25th August, respectively. Mean oviposited egg number was 59, and egg period was about 9 days. Hatching rate was >90%. Oviposited egg number was the highest in the first needle cluster of short shoot followed by second and third. P. itoi did not oviposit on single needle (long shoot) of Larix leptolepis (Sieb. et Zucc.). Larva had five instars, and larval period was about 20 days. Larva prefer needle cluster of short shoot to single needle of long shoot. Mature larva descended from host tree and pre-pupa in cocoon overwinter at topsoil.

• Korean journal of applied entomology
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• v.46 no.1 s.145
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• pp.1-4
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• 2007

Pachynematus itoi Okutani, belonging to the family Tenthredinidae(Hymenoptera), which infested Larix kaempferi(Lamb.) Carriere in the middle areas of Korea, is reported for the first time from Korea. External characteristics of adults are briefly redescribed with photos. Also its damages and bionomic data are discussed.