Arrhenotoky is a type of parthenogenesis in which unfertilised eggs develop into males. A spider mite or western flower thrips female that has never mated still lays eggs, but all become sons; once she mates she lays mostly daughters. It is the reproductive face of haplodiploidy.
In practice
For growers, arrhenotoky means a single female that survives a spray or arrives on a clone can found a population on her own, by producing sons and then mating with them. It is one reason quarantine and zero-tolerance clone policies matter: one survivor is enough.
Don't confuse with
- Thelytoky: unfertilised eggs become females (some thrips; aphids by live birth).
- Haplodiploidy: the genetic system behind it.
Reproduction without mating. Indoor aphids are all-female and give live birth to daughters that already carry developing embryos.Tetranychus urticae, the commonest cannabis mite indoors: a 0.5 mm sap-feeder that stipples leaves pale and spins webbing, breeding fastest in hot, dry rooms.Slender insects about 1-2 mm long, chiefly western flower thrips (Frankliniella occidentalis), that rasp leaf surfaces, leaving silvery streaks dotted with black frass.A sex-determination system where males develop from unfertilised eggs with one chromosome set and females from fertilised eggs with two; found in mites, thrips and whiteflies.Small soft-bodied sap-sucking insects of the family Aphididae that cluster on stems and leaf undersides, excrete sticky honeydew and multiply rapidly by live birth.The share of offspring that are female; because only females lay eggs, a female-biased ratio speeds population growth.
