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Ophelimus eucalypti and Ophelimus maskelli are gall wasps that are considered as a threat to the large Eucalyptus commercial plantations in Sumatra, Indonesia. However, they are partially suppressed by parasitoids including Closterocerus chamaeleon. The aim of this study was to evaluate the longevity and daily survival rate of O. eucalypti, O. maskelli and C. chamaeleon adults when receiving or not receiving food sources and also when reared in four different vial types under two environments (one environmentally controlled and another ambient), in a laboratory in Riau, Sumatra. The rearing test of C. chamaeleon as a biocontrol agent would be used for augmentative releases. We also evaluated the duration of the stages and the complete lifespan (egg → larva → pupa → adult) of O. eucalypti in a greenhouse in Porsea, North Sumatra, Indonesia, where this species is aggressive. With few exceptions, the longevity and survival rate of O. eucalypti, O. maskelli and C. chamaeleon adults was similar between the two conditions. The longevity and survival of C. chamaeleon were much greater than those of its gall wasp hosts, and of O. eucalypti greater than that of O. maskelli. Overall, these parameters were greater for gall wasps and the parasitoid reared in the larger vial types. The food source provided to O. maskelli adults did not however benefit the longevity of this gall wasp in the best tube type. The lifespan of O. eucalypti (mean ± SD of the mean) was 44 ± 6 days in a greenhouse. The much greater longevity and survival rate of C. chamaeleon than those of its hosts are facts that trigger the success of this insect as a gall wasp parasitoid. The higher longevity and survival of O. eucalypti compared to O. maskelli contribute to the higher threat status of O. eucalypti to Eucalyptus. [ABSTRACT FROM AUTHOR]

Mirid bugs (Hemiptera: Miridae) are important pests of Eucalyptus (Myrtaceae) trees in Indonesia. Young Eucalyptus plantations are mainly affected by Helopeltis spp. Damage by Helopeltis resulted in die-back of young shoots, curling, deformation and drying usually, irrespective of the clones. In North Sumatra, damage in Eucalyptus is associated to Helopeltis bradyi Waterhouse despite the presence of H. theivora Waterhouse in the region. Important alternate host plants recorded as reservoirs of H. bradyi in vicinity to Eucalyptus plantations were Persea sp. (Lauraceae), Coffea sp. (Rubiaceae), Psidium guajava (Myrtaceae), Ludwigia sp. (Onagraceae), Clidemia hirta (Melastomataceae) and Theobroma cacao (Malvaceae). Leiophron sp. (Hymenoptera: Braconidae) was reported as an important parasitoid with parasitism of 41.86% on the H. bradyi nymphs and 17.07% on adults. Helopeltis theivora was recorded as the only species affecting Eucalyptus plantations in Riau Province, so far no other Helopeltis sp. has been identified in Riau. Ragwelellus festivus Miller and Ragwelellus sp. were reported for the first time damaging Eucalyptus trees in North Sumatra, Riau Province and East Kalimantan regions of Indonesia. Arthriticus eugeniae Bergroth was also reported for the first time damaging matured Eucalyptus trees along with Ragwelellus in North Sumatra and Riau Provinces. [ABSTRACT FROM AUTHOR]