LIFE HISTORY AND BIOLOGY OFCTENARYTAINA THYSANURAFERRIS AND KLYVER (HEMIPTERA: PSYLLIDAE) ONBORONIA MEGASTIGMANEES EX BARTL. (RUTACEAE) IN TASMANIA

Abstract

The general biology of Ctenarytaina thysanura, an important pest of Boronia megastigma in plantations in Tasmania, was studied under glasshouse and field conditions from 1986–89. The psyllid passes through an egg and five nymphal stages. Eggs hatched in 11.5 d and nymphal development took 29 d under glasshouse conditions. Females oviposited preferentially in the leaf axils of the host plant's terminal shoots, and more than 55% of the eggs laid were deposited in the 3rd and 4th nodes within the terminal shoots. Adult longevity was 15.3 and 25.2 d for males and females, respectively. Males initiated mating and undisturbed copulations lasted for 30–40 min. Females laid an average of 85.6 eggs each with the majority of eggs laid between days 6 to 10. C. thysanura overwinters successfully on boronia plants in the egg and nymphal stages and, during mild winters, adults also overwinter. The egg and 1st to 3rd stage nymphs overwinter in the developing flower buds while the 4th and 5th stage nymphs overwinter in the leaf axils with the development of a dark pigment in the body surface. C. thysanura adults (males and females) fly together within boronia plantations and their flight activity was in response to peak densities of egg and nymphal stages. No egg parasitism was detected, but encyrtid parasitoids were found to attack C. thysanura nymphs. Coccinellids, spiders and syrphid fly larvae were the major predators observed feeding on the psyllid adults and nymphs. Copyright © 1993, Wiley Blackwell. All rights reserved