Introduction

Astigmatid mites form a suborder of the Acari, in the class Arachnida. Adult astigmatid mites are mostly oval or rod-like, less than 1 mm in length, and are opaque or transparent. Some species are economically important pests that attack a wide range of stored products and agricultural crops in fields and greenhouses. Others are common components of “house dust” and may contribute to health problems, causing atopic dermatitis and bronchial asthma. Most species, together with species in the suborder Oribatida, also function as scavengers of organic debris.

Pheromonal communication appears widespread among astigmatid mites. To date, the structures of 88 compounds, consisting of 26 monoterpenes, two sesquiterpenes, eight aromatic compounds, four aldehydes, a ketone, two novel fatty acids, a novel alkyl formate, and 14 fatty acid esters, have been conclusively identified from a total of 61 species of astigmatid mites belonging to 10 families, including 29 species that have not yet been formally described. Those unidentified species have been deduced to the genus level and are listed by the genus name with isolate names in parentheses, if necessary, such as Histiostoma sp. “shisetsu.” Many of the compounds are found in a number of different species, in which they may have different behavioral roles. For example, compounds that function as alarm pheromones in 19 species also form part of the aggregation pheromone blend in four species, and the sex pheromone in 14 species.