Tarsonemidae

Definition

A family of minute mites (Arachnida: Trombidiformes) commonly called thread-footed mites or white mites, characterized by reduced leg segmentation and often bearing a stout, claw-like empodium on the tarsi. Many species are economically significant plant pests (e.g., *Steneotarsonemus laticeps*, the bulb mite; *Polyphagotarsonemus latus*, the broad mite), while others are fungivores or parasitoids of insects. The family exhibits complex sexual dimorphism and life cycles often involving phoretic dispersal on insect vectors.

Etymology

From Greek tarso- (tarsus, ankle/foot) + nem- (thread), referring to the slender, thread-like legs characteristic of these mites.

Example

The broad mite *Polyphagotarsonemus latus* (Tarsonemidae) is a devastating pest of greenhouse peppers and strawberries, causing leaf distortion and fruit russeting through its feeding on young plant tissues.

Synonyms

• thread-footed mites
• white mites

Related Terms

• Trombidiformes
• Acari
• Phoresy
• empodium
• eriophyid mites
• bulb mite
• broad mite
• plant-feeding mites
• Prostigmata

Usage Notes

The common name 'white mites' is informal and can cause confusion with other pale mite groups; 'thread-footed mites' is preferred in technical contexts. Tarsonemidae is distinguished from the similarly plant-associated Eriophyidae (eriophyid or gall mites) by body shape—tarsonemids have a more compact, often sac-like idiosoma and lack the extreme elongation of eriophyids. Identification to species typically requires slide-mounting and examination of male genitalic structures. Some authorities place Tarsonemidae in the superfamily Tarsonemoidea within the clade Eleutherengona.