Notes on the biology of Anagrus breviphragma (Hymenoptera, Mymaridae), natural enemy of the corn leafhopper Dalbulus maidis (Hemiptera, Cicadellidae) and others plant diseases vectors in South America

Anagrus breviphragma Soyka 1955 is a wide distributed and polyphagous species that, in northern Argentina is a common egg parasitoid of the corn leafhopper Dalbulus Maidis De Long & Wolcott. Considering the lack of information about this wasp and the economic significance of its hosts, the purpose of this contribution was to provide data of its biology. A. breviphragma culture was established in a climatic cell (25 ± 2°C, 7075% RH and 14L:10D h of artificial photoperiod). Data obtained from distinct maturation stages of the exposed host eggs were analyzed. The eggs-laying behavior was described. This wasp is solitary and proovigenic, without a preovipositional period. A. beviphragma parasitized eggs that were only 1 -3 day-old, and was not able to mature in eggs containing advances embryos. In laboratory, the measured average of parasitims was 66.5%. The developmental time of A. breviphragma is around 16.5 days, and females reached the adult stage significantly faster than males. This species also developed faster in one-day-old eggs than in two-old, and in those of two-days-old faster than in three-days-old eggs. Adult longevity averages 5 days while few individuals surviving more than 12 days; females lived longer than males. The obtained sex ratio showed a predominance of melaes over males.