Tasty but Protected—First Evidence of Chemical Defense in Oribatid Mites

  title={Tasty but Protected—First Evidence of Chemical Defense in Oribatid Mites},
  author={Michael Heethoff and Lars Koerner and Roy A. Norton and G{\"u}nther Raspotnig},
  journal={Journal of Chemical Ecology},
Oribatid mites (Acari, Oribatida) represent one of the most abundant and speciose groups of microarthropods in the decomposer food webs of soils, but little is known of their top-down regulation by predators. Oribatids are relatively long-lived and have numerous morphological defensive adaptations, and so have been proposed to live in ‘enemy-free space’. Most also possess a pair of large exocrine oil glands that produce species-specific mixtures of hydrocarbons, terpenes, aromatics, and… 
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Specialized feeding of Euconnus pubicollis (Coleoptera: Staphylinidae: Scydmaeninae) on oribatid mites: Prey preferences and hunting behaviour
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The ontogeny of oil gland chemistry in the oribatid mite Archegozetes longisetosus Aoki (Oribatida, Trhypochthoniidae)
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Life as a fortress – structure, function, and adaptive values of morphological and chemical defense in the oribatid mite Euphthiracarus reticulatus (Actinotrichida)
Such an effective, holistic defense strategy, involving both morphological and chemical traits, probably carries high resource-costs, but it allows adult euphthiracaroid mites to occupy an almost “enemy-free space” despite the high diversity of predators in soil.
Regeneration of Complex Oil-Gland Secretions and Its Importance for Chemical Defense in an Oribatid Mite
Most oribatid mites possess a pair of opisthonotal exocrine glands that produce mostly complex, species-specific secretions. Such blends may contain more than 10 different compounds, but hardly
Community structure, trophic ecology and reproductive mode of oribatid mites (Oribatida, Acari) in forest ecosystems
Oribatid mites were used as model organisms to investigate the distribution of sexual and parthenogenetic individuals in forest soils in two regions in Germany and in different habitats worldwide in relation to food availability and the effects of nutrient availability on orib atid mite density and the frequency of parthenagenetic individuals on tree trunks.


Oil gland secretions in Oribatida (Acari)
Pheromonal properties of oil gland compounds probably evolved early in ancient oil gland-bearing oribatids from purely defensive functions, culminating in a radiation of semiochemical roles (alarm, aggregation, sex) in oil glands of the Astigmata.
Discrimination of Oribotritia species by oil gland chemistry (Acari, Oribatida)
The chemical composition of secretions from opisthonotal (oil) glands in four species of the oribatid mite genus Oribotritia was compared by means of gas chromatography—mass spectrometry and indicated the classification of euphthiracaroids within the (monophyletic) group of “Astigmata compounds-bearing”-Oribatida.
Specialized predation on Oribatid mites by two species of the ant genus Myrmecina (Hymenoptera: Formicidae)
Specialized predation on oribatid mites was confirmed in two Japanese species of the myrmicine genus Myrmecina, the first instance in the Formicidae. Using the mouthparts and legs, a worker
For Love of Insects
Recounting exploits and discoveries in his laboratory at Cornell and in the field in Uruguay, Australia, Panama, Europe and North America, Eisner demonstrates how inquiry into the survival strategies of an insect leads to clarifications beyond the expected.
Wearing a raincoat: exocrine secretions contain anti-wetting agents in the oribatid mite, Liacarus subterraneus (Acari: Oribatida)
The distinct extract profiles detected most likely portray the stepwise generation of an anti-wetting, exocrine surface lipid layer of glycerides: if this layer is lost, fatty acids may be discharged again (profile III) and may subsequently esterify (profile II) to larger and more stable esters (diacyl-glycerols), eventually building up the “raincoat” of L. subterraneus.
Chemical alarm and defence in the oribatid mite Collohmannia gigantea (Acari: Oribatida)
The multicomponent oil gland secretion of Collohmannia gigantea, a middle-derivative mixonomatan oribatid mite, is demonstrated to possess alarm pheromonal and allomonal properties, furnishing evidence for a phylogenetically early origin of defensive and communicative roles of oil gland secretions in o ribatids.
Adding to the Reproductive Biology of the Parthenogenetic Oribatid Mite, Archegozetes longisetosus (Acari, Oribatida, Trhypochthoniidae)
The gross morphology of the reproductive system as obtained by SEM techniques and X-ray synchrotron microtomography, a new tool for studying mite anatomy, is presented.
Role of musculature during defecation in a particle‐feeding arachnid, Archegozetes longisetosus (Acari, Oribatida)
This work uses a combination of non invasive microscopical techniques and in vivo examination to investigate the complex functional morphology of the anal region of the oribatid mite Archegozetes longisetosus Aoki, which is rather large in sarcoptiform mites.
Anatomy and function of the ptychoid defensive mechanism in the mite Euphthiracarus cooki (Acari: Oribatida)
Details of exoskeletal and muscular anatomy are examined in combination with studies of live individuals to provide the first functional analysis of ptychoidy, a defensive adaptation of several groups of oribatid mites.