Aceria chondrillae
Aceria chondrillae, also known as the chondrilla gall mite or skeletonweed gall mite, is a very small mite that forms galls on Chondrilla plants. It is used as a biological control to help manage the noxious weed Chondrilla juncea (skeletonweed), which naturally grows in Europe, Asia, Australia and North America.
At maturity, these mites are yellowish orange. Females are about 0.19–0.26 mm long, while males are a little smaller at about 0.165–0.180 mm. Larvae are even smaller, have a humpback shape, and lack external genitalia. Eggs are soft, round and about 0.04 mm in diameter; they start colorless and later become light orange. Development depends on environmental conditions, with an average generation time around 10 days.
When A. chondrillae infest Chondrilla plants, galls form. The galls look like clusters of tiny, hyperplastic buds and can reach 1.5–2 cm in diameter, sometimes up to 5 cm. Each gall can house hundreds of mites, all of which hinder the plant’s health, growth and ability to reproduce.
A. chondrillae affects several Chondrilla species, including C. juncea, C. juncea f. acantholepis, C. brevirostris and C. leiosperma. It is commonly released to help control skeleton weed in Europe, North America and Australia; Australia began using it in 1971 as part of weed-control efforts.
Predators in nature are rare. So far, only one predator has been observed: a Phytoseiid mite of the genus Amblyseius that lives inside the galls. These predators are uncommon and have little impact on A. chondrillae populations.
This page was last edited on 2 February 2026, at 23:59 (CET).