Two new species of Aulacaspis Cockerell, 1893 (Hemiptera: Coccomorpha: Diaspididae) from China

Two new armoured scale insects in the genus Aulacaspis (Hemiptera: Coccomorpha: Diaspididae) are described and illustrated from Guizhou Province, China. Aulacaspis paralonganae sp. n. was collected from the host-plant Schima superba (Theaceae) and A. guiyangensis sp. n. was collected from Cinnamomum camphora (Lauraceae). Aulacaspis longanae Chen, Wu & Su 1980 is redescribed and a new host-plant record is reported. The type specimens of the two new species and material of A. longanae are deposited in the Institute of Entomology, Guizhou University, Guiyang, China. An identification key based on adult females is provided to separate Chinese species of Aulacaspis.

A mutualism without honeydew: what benefits forMelissotarsus emeryiants and armored scale insects (Diaspididae)?

Mutualisms between ants and sap-sucking insects generally involve clear benefits for both partners: the ants provide protection in exchange for honeydew. However, a single ant genus associates with armoured scale insects (Diaspididae) that do not excrete honeydew. We studied three colonies ofMelissotarsus emeryiants from two localities in Mozambique. Vast numbers of the diaspididMorganella conspicuaoccupied galleries dug by the ants under the bark of living trees. Unlike free-livingM. conspicuaand other diaspidids,M. conspicualiving with ants are known to lack shields, likely because they gain protection against enemies and desiccation. Nevertheless, we documented the occurrence of rare individuals with shields inside ant galleries, indicating that their glands continue to secrete wax and proteins as building material. This is likely to constitute a significant portion of the ants’ diet, in addition to diaspidid exuviae and excretions from the Malpighian tubules. Indeed,Melissotarsusworkers cannot walk outside the galleries due to modified middle legs, forcing them to obtain all nourishment within the tree.Melissotarsusfounding queens, however, must locate a suitable host tree while flying, and acquire diaspidid crawlers. This mutualism involves ants that are highly specialised to chew through living wood, and diaspidids that can also live freely outside the bark. It is extremely widespread in Africa and Madagascar, recorded from 20 tree families, and harmful effects on plant hosts require rapid study.

The mutualism of Melissotarsus ants and armoured scale insects in Africa and Magadascar: distribution, host plants and biology

Species of the ant genus Melissotarsus Emery are widespread in the Afrotropical region (three species, namely M. beccarii Emery, M. emeryi Forel and M. weissi Santschi) and in the Madagascar region (one species, namely M. insularis Santschi). The ants of all these species tunnel their galleries in live wood of various dicotyledonous trees, close to the bark surface. The ants maintain within these galleries populations of different species of armoured scale insects. A review is presented on the geographical distribution of mutualism, of the Melissotarsus species, the associated 10 species of armoured scale insects, and the host plants on which the mutualism takes place. The ecology of the mutualism is discussed also, together with suggestions on the benefits that the partners gain from the associations.

Spirotetramat is toxic to leafrollers on kiwifruit

Spirotetramat is an ambimobile selective insecticide used widely in the horticulture industry for controlling a broad range of sucking pests in perennial and annual crops It has become the standard chemical for the control of armoured scale insects in kiwifruit During an experiment to test the effects of spirotetramat (formulated as Movento 100SC) on phytohormone levels it unexpectedly caused high levels of mortality to neonate brownheaded leafroller (Ctenopseustis obliquana) larvae (96 of treated plants with dead larvae compared with 9 in unsprayed controls) exposed one day after spraying to runoff on small potted A deliciosa Hayward plants Repeating the experiment with different plants and third instar larvae resulted in 98 treatment mortality compared with 29 on untreated controls A third experiment using neonate larvae applied to the same plants as the second experiment 10 days after the spray application resulted in 76 treatment mortality compared with 20 on control plants Spirotetramat can only be used preflowering and leafroller control sprays are applied principally during the first 6 weeks after fruit set However the potential contribution of spirotetramat to leafroller control on kiwifruit should be investigated further