How long do whirligig mites live? A survey of lifespan in Anystidae (Acari: Trombidiformes)

The Anystidae are a family of over 100 species of predatory mites commonly seen in soils and on plants worldwide. A few species of genus Anystis have potential as biocontrol agents against some insect and mite pests. Herein I provide a review of the lifespan of the Anystidae as part of a series on the lifespans in the Acari. The full life cycle in this family includes six immature stages (the egg, prelarva, larva, protonymph, deutonymph and tritonymph) and adult males/females. Life history data are only available for a few species. Developmental times from eggs to adults (44 to 82 days at 21 or 22 °C) were reported for three Anystis species. The total lifespan was measured for only one species (Anystis agilis): 66 days at 21 °C. There are two to three generations per year for Anystis species in the field. Summer aestivation was reported for Anystis baccarum, either as eggs or tritonymphs; aestivating tritonymphs may have a developmental time and total lifespan of over 200 and 300 days, respectively.

Efficacy of Anystis baccarum against Foxglove Aphids, Aulacorthum solani, in Laboratory and Small-Scale Greenhouse Trials

A generalist predatory mite, Anystis baccarum (L.), has been identified as a key predator of small, soft-bodied pest species in various agroecosystems around the world. The foxglove aphid Aulacorthum solani (Keltenbach) is a new problematic pest in Canadian greenhouses. Laboratory colonies of A. baccarum were established and its predatory efficacy against A. solani was assessed. In laboratory trials, A. baccarum ate approximately one adult aphid or seven first instar aphids in 24 h. In a greenhouse bench trial on sweet peppers with the free-flying aphid parasitoid, Aphidius ervi Haliday, the population dynamics of A. solani in the presence or absence of A. baccarum was evaluated. Although the parasitoid alone successfully eradicated A. solani, when A. baccarum were present on the plants, the aphid population was eradicated more rapidly. Fruit yield was also 15% higher from plants where A. baccarum was released than the control (without A. baccarum). Furthermore, plants were naturally infested by Frankliniella occidentalis (Pergande) during the trial, which caused visible feeding damage to the fruits. Anystis baccarum also predates on thrips and thrips’ feeding damage to the fruits was reduced on plants where A. baccarum was released. Anystis baccarum was able to establish in sweet peppers and was determined to be complementary to the current practice of using A. ervi for the biological control of A. solani.

Who ate all my leafrollers?

Leafrollers are pests of many fruit crops, and insecticides are used to control their numbers in commercial orchards. However, little is known about how much their natural enemies contribute to their control. Over two summers, larvae of two leafroller species were established in leaf rolls on potted poplar plants, which were placed along shelterbelts in 16 kiwifruit orchards. After a minimum of 38 hours, the leafrollers were retrieved and reared to determine parasitism rates and parasitoid identities. Egg batches and tethered larvae were also placed in the shelterbelts, with some monitored by video cameras, to determine predation rates and predator identities. Up to 3% of larvae in leaf rolls were parasitised in some orchards, by four different parasitoids, with the fly Trigonospila brevifacies accounting for the majority. Rates of predation were higher, with up to 40% of eggs, and 37.2% of larvae being taken. Fourteen different predator taxa were observed feeding on eggs and larvae, with the mite Anystis baccarum, earwigs, and spiders being the primary predators. Understanding which natural enemies are suppressing leafroller populations offers the potential for conserving or increasing those predator and/ or parasitoid numbers in cropping environments.

The effectiveness of two brushing systems for post harvest disinfestation of kiwifruit

The presence of some insect and mite species on kiwifruit at harvest can cause quarantine problems in some overseas markets There is potential to remove these passenger pests using physical handling methods such as the fruit brushing systems that are currently used in packhouses The abilities of two types of post harvest brushing systems to remove surface dwelling insects and mites from kiwifruit were compared Bins of naturally infested fruit were passed through two contrasting post harvest brushing systems and levels of infestations subsequently compared with unbrushed fruit Both brushing systems removed more than 85 of Collembola thrips mites and small beetles However armoured scale insects were not removed and a relatively low proportion of whirlygig mite (Anystis baccarum) cocoons was removed There were no significant differences between the two brushing systems