Fact-checked by Grok 2 weeks ago

Spider mite

Spider mites are tiny arachnids in the family Tetranychidae, part of the order Trombidiformes, encompassing over 1,200 described species across more than 70 genera, primarily in the subfamilies Tetranychinae and Bryobiinae.^[1] These microscopic pests, typically measuring 0.3 to 0.5 mm in length, possess eight legs as adults, an oval-shaped body, and specialized mouthparts for piercing plant cells to extract sap, often producing fine silk webbing on leaf undersides that gives them their common name.^[2]^[3] The life cycle of spider mites includes four developmental stages: egg, larva (with three pairs of legs), protonymph and deutonymph (both with four pairs of legs), and adult, which can complete in as little as 8–12 days under optimal hot, dry conditions (around 30°C).^[4]^[2] Adult females, which are generally larger than males and can live 2–4 weeks, lay 60–100 eggs over their lifetime, often exhibiting arrhenotokous parthenogenesis, in which unmated females produce male offspring from unfertilized eggs, while mated females produce female offspring from fertilized eggs (and males if unfertilized).^[3]^[2]^[5] Colors vary by species and life stage, ranging from pale green or yellow in active twospotted spider mites (Tetranychus urticae)—marked by two dark dorsal spots—to brick red in European red mites (Panonychus ulmi), with overwintering females often turning orange.^[6]^[3] Ecologically, spider mites thrive in warm, arid environments and have an extraordinarily broad host range, with species like T. urticae infesting over 1,100 plant species across 140 families, including major crops such as fruits, vegetables, ornamentals, and field crops like apples, tomatoes, beans, and corn.^[2]^[3] They disperse actively by walking or passively via wind, often building up populations rapidly in greenhouses or during droughts, leading to multiple generations (up to 20 per year) and significant economic damage through feeding that causes chlorotic stippling, leaf bronzing, defoliation, and reduced photosynthesis and yields.^[4]^[6] Notable pests include the twospotted spider mite, McDaniel spider mite (T. mcdanieli), and citrus red mite (Panonychus citri), which collectively account for substantial losses in agriculture and horticulture worldwide.^[2]^[6]

Taxonomy

Classification

Spider mites belong to the family Tetranychidae within the order Trombidiformes (formerly classified under the order Acarina), suborder Prostigmata, subclass Acari, class Arachnida, phylum Arthropoda, and kingdom Animalia.^[7] The family encompasses approximately 1,364 described species (as of November 2025), representing a significant portion of plant-feeding mites.^[8]^[9] The Tetranychidae are divided into two main subfamilies: Tetranychinae, which includes most plant-feeding species such as those in the genus Tetranychus, and Bryobiinae, which includes herbivorous species.^[10] The Tetranychinae are characterized by advanced traits like silk production for webbing, while Bryobiinae retain more primitive features, such as living primarily on leaf uppersides without extensive webbing.^[10] Key distinguishing traits of Tetranychidae from other mite families include the presence of empodia (terminal structures on the legs) equipped with tenent hairs, which facilitate adhesion to plant surfaces, and prodorsal trichobothria (sensory setae on the anterior dorsal shield), a feature typical of the Prostigmata suborder.^[11] These adaptations support their specialized phytophagous lifestyle, enabling efficient host colonization and movement.^[12] The evolutionary history of Tetranychidae reflects adaptations to terrestrial plants, with Bryobiinae exhibiting ancestral characteristics like anastomosed peritremes (respiratory structures) and reduced ambulacral claws, while Tetranychinae show innovations such as simple peritremes and pad-like ambulacra that enhance mobility on leaf undersides.^[10] Silk production in Tetranychinae represents a major evolutionary advancement, allowing protection and habitat modification, which has contributed to their diversification across diverse plant hosts including gymnosperms and angiosperms.^[10] The primary global database for Tetranychidae taxonomy is the Spider Mites Web (INRAE), which tracks ongoing updates to species counts, distributions, and host associations.^[8]

Genera and species

Spider mites belong to the family Tetranychidae, which encompasses 1,364 species (as of November 2025) distributed across temperate and tropical regions worldwide, with many exhibiting invasive tendencies facilitated by global trade since the 19th century.^[8]^[13] The most economically significant genera include Tetranychus, Panonychus, Oligonychus, and Bryobia, each featuring key pest species that inflict substantial damage on agricultural and ornamental crops. The genus Tetranychus comprises numerous polyphagous pests, with T. urticae (the two-spotted spider mite) standing out as a cosmopolitan species notorious for its broad host range of 1,577 plant species across 132 families (as of 2025), including ornamentals, fruits, and vegetables.^[14]^[15] This mite has achieved global distribution through human-mediated dispersal, originating from Europe and now prevalent in temperate and subtropical zones, where it causes severe leaf damage and yield losses in crops like strawberries, tomatoes, and chrysanthemums.^[16] T. urticae is particularly problematic due to its rapid development of resistance to numerous pesticides, complicating management efforts in both field and greenhouse settings.^[16] In the genus Panonychus, P. ulmi (the European red mite) is a major pest of fruit trees, favoring temperate climates and deciduous hosts such as apples, pears, cherries, and plums.^[17] Native to Europe and introduced to North America in the early 1900s, it has established across the United States and Canada, where populations peak in early and late summer, leading to leaf stippling, bronzing, and defoliation that reduce fruit quality and tree vigor.^[17] The genus Oligonychus includes O. punicae (the avocado brown mite), an important pest primarily on citrus and avocado in subtropical regions like southern California, Mexico, and parts of Africa and South America.^[18] This species feeds on over 120 plant types, causing defoliation, fruit drop, and sunburn on avocado crops, which results in significant economic losses for major producers like Mexico.^[18] Bryobia praetiosa (the clover mite) from the genus Bryobia is a widespread nuisance pest found across North and South America, Europe, Asia, Africa, and Australia, often invading structures near lawns and feeding on grasses, clovers, and ornamental flowers.^[19] While it causes minor plant damage like silver streaking on leaves, its primary impact stems from large aggregations staining indoor surfaces red when crushed.^[19] Less common but notable genera include Eotetranychus, with species like E. sexmaculatus (the six-spotted mite) acting as pests on citrus and avocado in North America, Asia, and Oceania, where it affects over 50 host species and poses risks to EU production if introduced.^[20] Similarly, Schizotetranychus species specialize on conifers and related plants, with distributions spanning Asia, Australia, and parts of Europe, occasionally damaging forestry and ornamental conifer hosts.^[21]

Description

Morphology

Spider mites exhibit a distinctive body structure typical of the family Tetranychidae within the order Trombidiformes. The body is divided into two primary regions: the gnathosoma, an anterior capitulum containing the mouthparts, and the idiosoma, the larger posterior region that encompasses the body proper and bears the legs. The overall form is oval or ovoid in adult females, measuring approximately 0.4–0.5 mm in length, while males are smaller and more tapered posteriorly.^[22]^[16]^[23] The mouthparts are adapted for piercing and sucking plant tissues. The chelicerae are modified into paired, elongate stylets—often recurved and J-shaped—that interlock to form a hollow, needle-like tube for penetrating cell walls and extracting contents. These stylets, with an inner diameter of about 1 μm, are housed within a stylophore formed by the fused cheliceral bases and are accompanied by palps that curve inward, featuring a thumb-claw complex for manipulation during feeding.^[22]^[24]^[23] Sensory structures enhance navigation and host interaction. Adult spider mites possess four pairs of legs, each equipped with trichobothria—specialized setae on the tarsi, tibiae, or other segments—that detect subtle air currents and vibrations for environmental sensing. For adhesion to smooth leaf surfaces, the pretarsi feature ambulacra comprising paired claws and a central empodium, often pad-like with tenent hairs and a dorsal spur in females, facilitating secure footing during feeding and movement. Larvae, in contrast, have only three pairs of legs.^[25]^[22]^[16]^[23] Silk production is a key adaptation, primarily in females of the subfamily Tetranychinae. Spinnerets, located on the tarsi of the palps, extrude fine silk threads used to form protective webs over feeding sites, aid in dispersal via ballooning, and shelter eggs or colonies.^[22]^[23]

Size and coloration

Spider mites are minute arachnids, with adults typically measuring 0.3 to 0.5 mm in length.^[26] Females are generally larger and more robust than males, reaching up to 0.5 mm, while males are narrower and measure about 0.3 mm.^[27]^[28] Coloration in spider mites varies widely depending on species, life stage, and environmental conditions, ranging from pale yellow or greenish hues in active summer forms to red or orange in overwintering diapausing individuals.^[29] In the common twospotted spider mite (Tetranychus urticae), active adults often display a pale yellow to green body with two prominent dark spots on the dorsum.^[6] Diapausing females of this species turn orange-red, a change linked to carotenoid accumulation for overwintering survival.^[30] Sexual dimorphism is evident in body shape, with females possessing rounded abdomens and males featuring tapered, pointed abdomens equipped with an aedeagus for sperm transfer during mating.^[31]^[32] Environmental factors, such as host plant and seasonal conditions, influence coloration; for instance, mites may adopt darker green or brown tones on certain hosts to enhance camouflage, and high-density populations under stress can lead to intensified pigmentation.^[33]^[34]

Life cycle

Developmental stages

The developmental stages of spider mites, exemplified by the twospotted spider mite (Tetranychus urticae), encompass the non-reproductive phases from egg to adult, including active feeding periods interspersed with quiescent molts. These stages occur rapidly under favorable conditions, allowing multiple generations per growing season.^[35]^[4] Eggs are spherical, measuring 0.1–0.15 mm in diameter, and initially translucent and whitish, becoming opaque and straw-colored with visible carmine eyespots as incubation progresses. They are laid singly on the undersides of leaves, often within fine silk webbing produced by the female, and hatch in 3–6 days depending on temperature, typically 3–5 days at 25°C.^[4]^[35]^[6] The subsequent larval stage is hexapod, with three pairs of legs, and the body resembles a smaller version of the adult (approximately 0.14 mm long) but lacks genital structures. Larvae emerge colorless with red eyespots, turning pale green, yellowish, or pinkish after active feeding on plant sap, with this stage lasting 1–3 days.^[4]^[35]^[6] A non-feeding quiescent period known as the protochrysalis follows, during which the larva molts; this resting phase lasts from hours to about a day. The protonymph then emerges, octopod with four pairs of legs, larger than the larva (pale to dark green with developing dorsal spots), and feeds actively for 1–3 days while body structures enlarge.^[35]^[4] Another quiescent deutochrysalis molt, also non-feeding and brief (hours to a day), precedes the deutonymph stage. The deutonymph is the largest immature form, eight-legged, and lasts 1–3 days, with further size increase and the onset of reproductive organ development, especially in individuals destined to become adults.^[35]^[4] Temperature profoundly influences stage durations, with the full cycle from egg to adult completing in 8–12 days at around 30°C but extending to 17 days or more at 20°C and halting below a lower threshold of approximately 12°C.^[4]^[35]

Reproduction

Spider mites primarily reproduce through sexual means, with males transferring sperm directly to the female's genital opening via the aedeagus, a specialized intromittent organ.^[36] In many species, including Tetranychus urticae, reproduction follows an arrhenotokous parthenogenetic system, where fertilized eggs develop into females and unfertilized eggs produce males, allowing virgin females to initiate populations by laying male-only offspring.^[5] This haplodiploid mechanism enhances colonization potential, as a single female can produce sons that subsequently mate with her to generate daughters.^[37] Fecundity in female spider mites varies by species and conditions but typically ranges from 20 to 100 eggs laid over 2 to 4 weeks, with the highest oviposition rates occurring in the first week after maturity.^[38] For instance, in T. urticae, mated females can deposit up to 100 eggs during their adult lifespan, often at a peak of around 20 eggs per day early in the oviposition period.^[39] Egg-laying initiates the reproductive cycle, with eggs typically deposited singly on leaf undersides near feeding sites.^[40] Mating behaviors in spider mites are aggressive and involve male guarding of pre-adult females, guided by female sex pheromones released from quiescent deutonymphs to attract males.^[41] In some Tetranychus species, males exhibit behaviors that facilitate rapid insemination, such as removing the female's exuvia immediately after ecdysis to expose the genital opening, ensuring they secure the first mating opportunity.^[42] Asexual reproduction occurs in specific strains of T. urticae through thelytokous parthenogenesis, where unfertilized eggs develop into females, resulting in all-female offspring and enabling rapid, clonal population expansion without males.^[43] This mode, often linked to endosymbionts like Wolbachia or Cardinium, provides a short-term advantage in stable environments by avoiding the costs of sex.^[44] Reproduction can be interrupted by diapause, a photoperiodically induced arrest triggered by short day lengths (typically less than 12-14 hours), leading to dormant, non-feeding adult females that turn bright red or orange.^[45] These diapausing forms overwinter without oviposition, resuming reproductive activity upon exposure to longer days in spring.^[46]

Hosts and damage

Plant hosts

Spider mites exhibit a wide range of host specificity, with polyphagous species such as Tetranychus urticae capable of infesting over 1,100 plant species across more than 140 families.^[15] This broad host range encompasses diverse categories, including ornamental plants like roses and chrysanthemums, vegetables such as tomatoes and beans, and fruits including strawberries and citrus.^[47] In contrast, other species display narrower preferences; for instance, Oligonychus ilicis (southern red mite) is primarily associated with hollies (Ilex spp.), particularly Japanese holly (I. crenata), though it may occasionally affect related ornamentals like azaleas and camellias.^[48] Similarly, Panonychus citri (citrus red mite) shows oligophagous tendencies, favoring citrus species but also infesting over 100 other plants including almonds, pears, and roses, with citrus serving as the primary economic host.^[49] Spider mites feed by inserting their cheliceral stylets into mesophyll cells of host leaves, injecting salivary enzymes that liquefy cell contents for extraction, which leads to localized cell collapse and content removal from individual or adjacent cells along the stylet path.^[50] They exhibit clear feeding preferences, favoring succulent young leaves due to higher nutrient availability and tenderness, often colonizing the undersides where conditions are more protected.^[51] Factors influencing host selection include physical barriers; mites tend to avoid surfaces with dense pubescence (hairs or trichomes) that hinder movement and attachment, as seen in resistant varieties where increased leaf hairiness correlates with reduced oviposition and establishment.^[52] Waxy cuticles on leaves also act as a deterrent by forming a physical barrier that impedes stylet penetration and mite adhesion.^[53] Host damage by spider mites is particularly severe in controlled environments like greenhouses, where warm, dry microclimates promote rapid population growth on susceptible crops, and in arid regions, where low humidity and plant stress exacerbate infestations across a variety of hosts.^[33]

Symptoms and economic impact

Spider mite infestations cause visible damage to plants primarily through their feeding activity, where mites pierce leaf cells and extract contents, leading to cell death and characteristic stippling—small yellow-white dots on the upper leaf surface.^[54]^[55] As feeding intensifies, affected leaves develop a bronzed or dusty appearance, and severe infestations result in yellowing, browning, and premature leaf drop.^[54]^[56] Heavy webbing produced by the mites often covers colonies, providing shelter and facilitating spread, particularly on the undersides of leaves.^[57] Physiologically, spider mite feeding disrupts plant processes by removing chlorophyll and plant sap, reducing net photosynthetic rates by up to 50% in heavily infested leaves, such as in cucumbers after 1,000 mite-days per 6 cm² or in strawberries with high late-season populations.^[58]^[59] This leads to stunted plant growth, decreased overall vigor, and premature fruit drop in affected crops.^[60] While spider mites can acquire certain plant viruses like tobacco mosaic virus during feeding, transmission to new plants is rare and typically incidental rather than efficient vectoring.^[61]^[62] Economically, spider mites inflict substantial losses in agriculture, particularly on crops such as cotton, soybeans, and apples, where Tetranychus urticae infestations in untreated fields can cause 20–30% yield reductions in cotton and up to 40–60% in soybeans.^[63]^[40] In apples, mite damage reduces fruit quality and tree growth, contributing to broader production losses.^[64] Major outbreaks in the U.S. cotton belt during the 1940s, exacerbated by organochlorine pesticides disrupting natural predators, prompted innovations in mite-specific control strategies.^[65] Climate change is projected to exacerbate spider mite incidence by favoring warmer, drier conditions that accelerate their life cycles and population growth, potentially increasing outbreak risks in agricultural regions.^[66]^[67] As of 2025, reports indicate expectations of moderate to heavy infestations in crops such as almonds, grapes, and tree fruits in arid areas like California due to ongoing dry conditions.^[68]^[69] Early detection is crucial for mitigating damage and can be achieved using a 10x hand lens to inspect leaves for mites, eggs, and fine webbing, or by tapping foliage over white paper to observe dislodged specimens.^[70]^[31]

Control measures

Biological control

Biological control of spider mites relies on natural enemies, including predatory arthropods and microbial agents, to suppress pest populations in agricultural and horticultural settings. These biotic agents are particularly valuable in integrated pest management programs, where they target spider mites without the environmental drawbacks of chemical interventions. Key strategies involve both augmentative releases of mass-reared predators and conservation tactics to support resident natural enemies. Predatory mites from the family Phytoseiidae are among the most effective biological control agents against spider mites, such as Tetranychus urticae. Phytoseiulus persimilis, a specialist predator, primarily feeds on eggs and immature stages of spider mites and can consume 5–20 prey items per day as an adult, enabling rapid population suppression under favorable conditions of 62–80°F and 50–70% relative humidity.^[71]^[72] In contrast, Neoseiulus californicus functions as a generalist predator, capable of surviving and reproducing on alternative foods when spider mite densities are low, making it suitable for preventive applications in diverse crops like tomatoes and strawberries.^[73]^[74] Other invertebrate predators include lady beetles of the genus Stethorus, lacewings (Chrysoperla spp.), and predatory thrips, which consume all life stages of spider mites and complement mite predators in field and greenhouse systems. These agents are typically released at rates of 2–10 individuals per square meter to establish populations in infested areas, with repeated applications enhancing control during outbreaks.^[46]^[75] Parasitoids are rare for spider mites, but entomopathogenic fungi such as Beauveria bassiana serve as biopesticides, infecting and killing mites through direct contact or spore inhalation. Applications of B. bassiana isolates have achieved mortality rates of 70–90% in T. urticae populations, particularly against larvae, with efficacy increasing under high humidity.^[76] Augmentative biological control programs, involving the mass release of predators like P. persimilis, have been commercially available since the 1960s and are highly effective in enclosed environments such as greenhouses, where they suppress T. urticae with success rates exceeding 80% when released at 20,000–200,000 per acre early in infestations.^[77]^[78] These releases exploit the predator's faster developmental rate and higher reproductive potential compared to the pest, leading to prey eradication in controlled settings.^[77] Conservation tactics enhance endogenous predator populations by providing alternative resources, such as pollen from plants like cattail (Typha latifolia) or corn (Zea mays), which sustain generalist mites like N. californicus during prey scarcity and improve long-term suppression of spider mites in crops such as cucumbers and tomatoes.^[79]^[80]

Chemical control

Chemical control of spider mite infestations primarily relies on acaricides, which are pesticides specifically targeting mites through various modes of action. These compounds are categorized based on their penetration and activity: contact acaricides act on direct exposure, systemic ones are absorbed by plants for internal distribution, and ovicides target eggs. For instance, abamectin, a contact and translaminar acaricide from the avermectin class (IRAC Group 6), binds to glutamate-gated chloride channels, causing paralysis and death in motile stages of spider mites like Tetranychus urticae. Spiromesifen, a systemic acaricide (IRAC Group 23), inhibits acetyl-CoA carboxylase, disrupting lipid biosynthesis and leading to desiccation across all life stages. Chlorfenapyr, effective as an ovicide and broad-spectrum agent (IRAC Group 13), uncouples oxidative phosphorylation, depleting cellular energy and killing eggs, immatures, and adults.^[81]^[82] Application methods emphasize foliar sprays applied to the undersides of leaves for thorough coverage, typically at intervals of 7–14 days depending on infestation severity and product residual activity. Rotation among acaricides with different modes of action is essential to delay resistance development, and treatments are initiated at integrated pest management thresholds of 5–10 motile mites per leaf to balance efficacy and minimize unnecessary applications. Adjuvants such as surfactants may enhance penetration, but adherence to label rates and pre-harvest intervals is required to avoid phytotoxicity or residues.^[3]^[83] Resistance in T. urticae poses a major challenge, with the species having developed resistance to over 90 different acaricide compounds since the 1950s, primarily through enhanced metabolic detoxification via cytochrome P450 enzymes and other mechanisms. This rapid evolution, documented in global populations, underscores the need for resistance monitoring and diversified strategies. Regulatory restrictions have further limited options; for example, dicofol, once widely used against spider mites, was phased out in the United States by the early 2010s due to its environmental persistence, high mammalian toxicity, and similarity to the banned DDT.^[84]^[85] When applied correctly at labeled rates, acaricides like abamectin and spiromesifen can reduce spider mite populations by up to 90% within 3–5 days, providing rapid suppression in crops such as ornamentals and vegetables. However, overuse or improper rotation often leads to secondary outbreaks by disrupting natural enemy populations, highlighting the value of integrating chemical controls with biological agents for sustainable management.^[86]^[87]

Cultural and environmental controls

Cultural and environmental controls for spider mites emphasize preventive farm management practices that disrupt mite life cycles and create unfavorable conditions without relying on chemical interventions. Maintaining optimal environmental conditions is crucial, as spider mites thrive in hot, dry environments with relative humidity below 40% and temperatures exceeding 32°C (90°F). Growers can mitigate outbreaks by sustaining relative humidity between 50% and 70% through practices like misting systems in greenhouses or ensuring adequate soil moisture in field crops, while avoiding excessive heat buildup via shading or ventilation.^[88]^[89]^[90] Cultural practices further support mite suppression by enhancing plant vigor and reducing habitat suitability. Overhead irrigation, applied periodically as a strong water jet or syringing, physically dislodges mites from foliage and increases local humidity, thereby slowing population growth. Pruning dense canopies improves airflow, reducing microclimates conducive to mite proliferation, while systematic removal of weeds eliminates alternate hosts that harbor overwintering mites and facilitate reinfestation. These measures, when integrated into routine farm operations, help maintain low mite densities before they reach damaging levels.^[33]^[31]^[6]^[91] Application of harpin proteins, such as Harpin Alpha-Beta, serves as a non-chemical elicitor that induces systemic acquired resistance (SAR) in plants, bolstering defenses against mite feeding. In strawberry trials, biweekly foliar applications reduced mite incidence to zero on treated leaves compared to controls, effectively preventing damage through enhanced phenolic metabolism and photosynthetic efficiency for up to several weeks post-application. This approach activates plant immune pathways without direct toxicity to mites, offering a sustainable option for protected cropping systems.^[92] Crop rotation and selection of resistant varieties provide long-term prevention by breaking host continuity and leveraging genetic resistance. Rotating soybeans or other susceptible crops with non-host plants like cereals disrupts mite carryover, while planting mite-resistant cultivars—such as those identified through screening programs initiated in the 1970s—minimizes infestation risk. For instance, glabrous or low-pubescent soybean lines exhibit reduced mite reproduction and feeding damage due to altered leaf surface properties, with breeding efforts since the 1980s incorporating such traits into commercial varieties.^[93]^[46] Effective monitoring through regular scouting protocols enables timely intervention at economic thresholds, typically 10-20 mites per leaf depending on crop value. Visual inspections of leaf undersides, combined with tapping branches over white paper to detect motile mites, allow growers to assess populations weekly during peak risk periods like hot, dry summers. Although sticky traps are less effective for non-flying spider mites, they can supplement scouting by capturing dispersing individuals in greenhouses, guiding decisions on when to intensify cultural controls. These integrated practices can be briefly combined with chemical options for comprehensive management when thresholds are approached.^[94]^[90]^[95]

References

[1]
Species identification of spider mites (Tetranychidae: Tetranychinae)
The Tetranychidae family is subdivided into two subfamilies, Bryobiinae and Tetranychinae, and includes at least 71 genera and more than 1250 described species, ...Missing: authoritative | Show results with:authoritative
[2]
[PDF] Introduction to Spider Mite Biology and Ecology
Spider Mites (Tetranychidae). • Many species (more than 1,200). • Generally, live on underside of leaves and produce webbing. • Chlorotic spots on the leaves.Missing: authoritative sources
[3]
Spider mites - Agricultural Biology
Their oval-shaped bodies range in color from green to yellow when active, or bright orange during dormant periods. Under magnification, two dark blotches are ...Missing: characteristics authoritative
[4]
[PDF] Spider mites (Order: Acari, Family: Tetranychidae) - UGA Extension
Actively feeding females are clear to greenish with dark spots on the body (except tumid mite). The tumid mite female is usually reddish with dark markings.<|control11|><|separator|>
[5]
Spider Mites | WSU Tree Fruit | Washington State University
The larva is round, about the same size as the egg, and has three pairs of legs. Initially it also is translucent (except the red eyespots), but once it begins ...Missing: authoritative | Show results with:authoritative
[6]
Spider Mites - Family Tetranychidae - BugGuide.Net
Classification. Kingdom Animalia (Animals). Phylum Arthropoda (Arthropods). Subphylum ... Order Trombidiformes. Suborder Prostigmata (Prostigs). Infraorder ...
[7]
The Jean Gutierrez spider mite collection - PMC - NIH
Mar 23, 2015 · The family Tetranychidae (spider mites) currently comprises 1275 species and represents one of the most important agricultural pest families ...
[8]
[PDF] Evolutionary changes in the Tetranychidae - Horizon IRD
The production of silk and webbing has had a revolutionary significance for the evolution of spider mites and many of the great differences between Bryobiinae ...Missing: Mesozoic | Show results with:Mesozoic
[9]
[PDF] Mites of Greenhouses Identification, Biology and Control
Tenent hairs: Slender hairs arising from claws or empodia, thought to allow mites to hold on to leaf surface; their distal end often slightly enlarged in ...
[10]
Tetranychidae, Tetranychinae - Acariformes - Lucid key
Tetranychoidea: Tetranychidae, Tetranychinae. Superorder Acariformes. Order Trombidiformes. Suborder Prostigmata. Supercohort Eleutherengonides.
[11]
Tetranychidae - an overview | ScienceDirect Topics
Tetranychidae refers to a family of arachnids, commonly known as spider mites, which includes more than 1000 species characterized by their similar ...
[12]
A link between host plant adaptation and pesticide resistance in the ...
Dec 17, 2012 · T. urticae is an extreme polyphagous pest with more than 1,100 documented hosts and has an extraordinary ability to develop pesticide resistance ...
[13]
Twospotted Spider Mite, Tetranychus urticae Koch (Arachnida: Acari
Economic Importance. All mites have needle-like piercing-sucking mouthparts. Spider mites feed by penetrating the plant tissue with their mouthparts and are ...
[14]
European Red Mite | USU
Infestations of European red mite are somewhat sporadic in Utah orchards; however, infestations can be severe and cause substantial crop and tree injury. Unlike ...
[15]
https://www.pnas.org/doi/10.1073/pnas.1213214110
[16]
Clover Mite Bryobia praetiosa Koch - University of Florida
Clover mites are widely distributed in North and South America, Europe, Asia, Africa, and Australia. Description. Adults. The adults are reddish brown to a dark ...
[17]
Pest categorisation of Eotetranychus sexmaculatus - PMC
Mar 29, 2023 · E. sexmaculatus feeds on more than 50 hosts in 20 botanical families and can be a serious pest of important crops in the EU such as citrus ( ...
[18]
Schizotetranychus mansoni - Spider Mites Web species
Type host: Oryza sativa. Type distribution: India. Summary. Nomenclature; Identification; Hosts; Distribution; Literature; Distribution Map (opens a new window) ...
[19]
None
### Summary of Spider Mite Morphology (Tetranychidae)
[20]
[PDF] Spider Mites - CABI Digital Library
Spider mites belong to the family Tetranychidae of the order Prostigmata. They are so named because many members of this family produce silk.Missing: authoritative | Show results with:authoritative
[21]
The Digestive System of the Two-Spotted Spider Mite, Tetranychus ...
Sep 10, 2018 · The stylet is composed of two cheliceral digits that interlock when protracted, forming a hollow tube-like organ (Andre and Remacle, 1984).<|separator|>
[22]
Ontogeny and evolution of the duplex trichobothria of ...
This type of arrangement has evolved independently in three groups of actinotrichid mites, affecting the prodorsal trichobothria of certain genera of the mite ...
[23]
Two-spotted Spider Mites (Corn) - Purdue Agriculture
Jul 29, 2025 · ... adult. Adult – The adult female is eight-legged and about 1/60 inch (0.4 mm) long. The eight-legged male is only about 1/80 inch (0.3 mm) long.
[24]
The various stages of the spider mite - Koppert US
Mar 4, 2023 · Adult females are half a millimeter in size, and their bodies are oval in shape. Males are smaller and narrower, with a slightly pointed back.
[25]
[PDF] Does size matter? Fecundity and longevity of spider mites ... - Biotaxa
Sep 3, 2018 · The female spider mites were significantly larger than males, with the female being about 480 μm and male being 325 μm in dorsal length (Fig. 3 ...
[26]
Tetranychus urticae : Insect & Mite Guide - UMass Amherst
The twospotted spider mite is approximately 1/50th of an inch in length, oval, and varies in color from orange-red or brown to green or greenish-yellow.
[27]
Horizontally transferred fungal carotenoid genes in the two-spotted ...
Sep 14, 2011 · Both genes are more highly expressed in red than in green spider mites, and exhibit changes in expression during diapause.<|separator|>
[28]
Spider Mites and Their Control | Ohioline
Sep 20, 2011 · Most spider mites have the ability to produce a fine silk webbing. Spider mites are very tiny, being less than 1/50 inch (0.4 mm) long when ...
[29]
Two-spotted spider mite - Biocontrol, Damage and Life Cycle
Size and shape: Spider mites are tiny, adults are about 0.5 mm long in length. They have an oval-shaped body with eight legs, which distinguishes them from ...
[30]
Spider Mites | Colorado State University Extension Website
Dec 1, 2014 · Their colors range from red and brown to yellow and green, depending on the species of spider mite and seasonal changes in their appearance.
[31]
https://ohioline.osu.edu/factsheet/HYG-2012-11
[32]
Biological Control - Section 2
Adult mites characteristically possess 4 pairs of legs compared to 3 pairs in insects (larval mites do however possess 3 pairs of legs). Virtually all adult ...Missing: four | Show results with:four
[33]
Ontogenetic and morphological studies on Tetranychus canadensis ...
Sep 28, 2020 · Systematic Entomology Laboratory (SEL), Beltsville Agricultural Research Centre (BARC), Maryland, 20705, USA. Acari spider mite T. ... aedeagus ...
[34]
Demographic analysis of arrhenotokous parthenogenesis and ...
Feb 20, 2018 · In arrhenotokous reproduction, virgin females initially produce male offspring; later, when their sons are sexually mature, the mothers begin ...
[35]
Mating Modifies Female Life History in a Haplodiploid Spider Mite
Spider mites present the additional advantage of being haplodiploid, so that virgin females can reproduce by laying unfertilized eggs that become male offspring ...
[36]
https://www.mapress.com/zt/article/view/zootaxa.4857.1.11
[37]
(PDF) Study on the developmental Stages of Spider Mite ...
Aug 5, 2025 · They found that the life cycle averaged within 10.6 to 14.4 days and a female laid 35.2 to 77 eggs. They also observed that the life cycle was ...
[38]
Twospotted Spider Mites | Integrated Crop Management
Aug 1, 2022 · Eggs of twospotted spider mites are laid singly on the underside of leaves. They are 0.14 mm long and become white as they age. Just before ...Missing: fecundity | Show results with:fecundity
[39]
Pheromone Studies of the Two spotted Spider Mite. 1. Evidence of a ...
Abstract. Male Tetranychus urticae Koch are attracted strongly to quiescent deutonymphs and will remain until emergence of the adult female, when mating occurs.
[40]
Spider mite males undress females to secure the first mating
Jul 21, 2023 · Spider mite males undress females by removing their exuvia during ecdysis, exposing their genital opening to secure the first mating.
[41]
Interspecific interactions between two predatory mites of the mould ...
An unpaired, cuticle-lined ejaculatory duct opens into the apex of the aedeagus. ... One of them was submitted to spider mite evaluation shortly after collection ...
[42]
Parthenogenesis in Mites and Ticks (Arachnida: Acari)
Thus, an unfertilized female of Tetranychus urticae gave rise to a female offspring which provided several generations of thelytokous progeny before the clone ...<|separator|>
[43]
Cardinium is associated with reproductive incompatibility in the ...
Cardinium was not present in the T. urticae prey and only was present in adult females and eggs from some populations of M. occidentalis. The amounts of ...
[44]
Twospotted Spider Mite, Tetranychus urticae - Wisconsin Horticulture
They range in color from light yellow or green to dark green or brown and at times can be bright red. All have two dark spots visible on the abdomen. Males are ...Missing: variations | Show results with:variations
[45]
Spider Mites / Strawberry / Agriculture: Pest Management ... - UC IPM
Diapause is indicated by a change in color to bright orange. In coastal growing areas it is rare to have a significant proportion of the population undergo ...
[46]
The genome of Tetranychus urticae reveals herbivorous pest ...
Nov 23, 2011 · ... tomatoes, peppers, cucumbers, strawberries, maize, soy, apples, grapes and citrus. The recent introduction of the related species Tetranychus ...
[47]
Holly Diseases & Insect Pests - Clemson HGIC
Sep 13, 2024 · Southern Red Mite: Southern red mite (Oligonychus ilicis) is an important pest of hollies, especially I. crenata 'Convexa', a Japanese holly. ...
[48]
Citrus red mite - UC IPM
Damage. Citrus red mite feeds on more than 100 plant species including almond, pear, and rose, but it is only a pest on citrus. Adults and nymphs suck cell sap ...Identification · Life Cycle · Damage · Solutions
[49]
Dissection of the Cellular Pattern of Tetranychus urticae Feeding on ...
Jul 27, 2016 · Spider mite feeding results in the removal of the content of a single or limited number of mesophyll cells that were on stylet path. In some ...
[50]
The distribution of herbivores between leaves matches their ... - NIH
Jul 9, 2020 · We investigated this in two herbivorous spider mites sharing tomato plants: Tetranychus . ... urticae to still prefer young leaves when those were ...
[51]
Twospotted Spider Mite / Caneberries / Agriculture - UC IPM
Varieties with heavily pubescent leaves can make establishment difficult for twospotted spider mites and may be useful for those situations where twospotted ...
[52]
Mechanisms of plant defense against insect herbivores - PMC
The first line of plant defense against insect pests is the erection of a physical barrier either through the formation of a waxy cuticle ... spider mites (Acari: ...
[53]
Twospotted spider mites in home gardens | UMN Extension
They use piercing-sucking mouthparts to feed on the sap on the underside of leaves and needles. This injury produces tiny white or yellow spots, giving leaves ...Missing: preferences hairy
[54]
Spider Mites | Home and Garden Education Center
Initial symptoms are small yellow or whitish stippling (spots) that appears on the foliage where chlorophyll has been removed.
[55]
Spider Mites - Urban IPM | Montana State University
Spider mites pierce plant cells and suck the sap out, causing flecking injuries and yellowing. They also cause premature leaf drop.
[56]
Spider Mites on Landscape Plants - UK Entomology
Spider mites (family: Tetranychidae) have a simple, oval‑shaped body and no wings or antennae. All species pass through an egg stage, a six‑legged larval ...
[57]
Leaf cell and tissue damage of cucumber caused by twospotted ...
At 1,000 mite-days per 6 cm2, net photosynthetic rate was reduced by approximately 50 and 95%, total chlorophyll content was reduced by approximately 55 and 80% ...
[58]
[PDF] Spider mites can reduce strawberry yields - UC ANR Portal
Photosynthesis and transpiration rates were as much as 50 percent lower in plants wth high late-season populations than in plants where mites were suppressed ( ...
[59]
Spider Mites on Apples and Pears - Pest Prophet Blog
Mite damage decreases photosynthetic rates which indirectly cause yield loss, decrease quality and can also negatively affect the return crop.
[60]
[PDF] Relationships with Tetranychus urticae
Tobacco mosaic virus, potato virus X, onion yellow dwarf virus and tomato bushy stunt virus are acquired by the two-spotted spider mite, but they are not ...
[61]
(PDF) Studies on the Transmission of Plant Viruses by Tetranychus ...
Mar 3, 2025 · Although viral particles have been observed in the mite's digestive system and feces, these interactions are considered incidental rather than ...<|separator|>
[62]
[PDF] Impact of Early Infestation of Two-Spotted Spider Mites (Tetranychus ...
Two-spotted spider mites remaining on cotton at damaging densities for two weeks or more regardless of infestation time, caused significant yield loss. However, ...
[63]
Effect of two-spotted spider mite population (Tetranychus urticae ...
Tetranychus mites' infestation of apple leaves causes economic losses in apple production due to reduced fruit quality, poor growth of trees, and reduced ...<|control11|><|separator|>
[64]
[PDF] Cotton Insects and Mites
Unfortunately, use of organochlorines released spider mites from their biological control agents and outbreaks became widespread (Anonymous, 1947-71; Boyer and ...
[65]
Impact of global warming scenarios on life-history traits of ...
Nov 27, 2019 · Life tables. A steeper decline in the age-specific survival rate (lx) curve was observed in mites under RCP8. 5 in June and August (Fig. 3) ...Missing: incidence | Show results with:incidence
[66]
[PDF] Impacts of climate change on tomato, a notorious pest and its natural ...
Aug 12, 2019 · Model predictions suggest that two-spotted spider mite potential for outbreaks would increase substantially in nine countries in Europe, Africa ...
[67]
Complete Guide to Spider Mites - Pest Prophet Blog
For most people, a 10x hand lens is needed to positively identify mites to the species level. For quantitative sampling, differentiating between adult, juvenile ...
[68]
Phytoseiulus persimilis–Predatory Mite - Cornell CALS
Phytoseiulus persimilis is a predatory mite used for spider mite biocontrol, targeting eggs and larvae, and is a popular, selective predator.
[69]
https://agnetwest.com/year-spider-mite-strategies-tree-nut-grape-growers/
[70]
Neoseiulus californicus–Predatory Mite - Cornell CALS
Rate: Most predatory mites are recommended to be released at a 1:10 predator to pest ratio for maintenance of low pest densities, and a 1:5 ratio for control of ...
[71]
Predatory Mite, Neoseiulus californicus (McGregor) (Arachnida: Acari
In strawberry, a release rate of one female Neoseiulus californicus per 10 twospotted spider mites is recommended once mites are present. A predator in first ...
[72]
Phytoseiulus persimilis - Predatory Mite for Spider Mite Control
Introduction rates typically range from 2-50 per m2/release. Releases should be repeated once or twice at weekly intervals. Consult a Koppert advisor or a ...
[73]
Compatibility of the entomopathogenic fungus Beauveria bassiana ...
bassiana Naturalis-L obtained mortality rates from 75% (Alves et al., 2002, Shi and Feng, 2009) to 97% (Chandler et al., 2005). On the other hand, Gatarayiha et ...
[74]
Phytoseiulus persimilis - Section 3
Since these initial studies, the ability of this predator to control twospotted spider mites has been demonstrated on many plants, including cucumber (Gould ...<|separator|>
[75]
Biological Control of Spider Mites in Tomatoes | NC State Extension
Phytoseiulus persimilis is a specialist predator of spider mites, such as the twospotted spider mite (TSSM, Tetranychus urticae Koch). It is a highly voracious ...Background · Distribution · Description · Use in Biological Control
[76]
Applying pollen over a crop as an alternative food source for ...
Jan 20, 2015 · Cattail pollen is an effective supplemental food source for predatory mites in some cropping systems. However, the strategy is still debated among scientists.Missing: conservation | Show results with:conservation
[77]
Neoseiulus cucumeris–Predatory Mite | NYSIPM Biocontrol Fact Sheet
Catttail pollen (Typha latifolia) and/or high-pollen producing banker plants such as peppers can be provided as an alternative food source on pollen-poor crops.
[78]
[PDF] The Insecticide and Miticide Mode of Action Field Guide1
Often, several chemical classes share the same mode of action because they kill insects and mites through the same biochemical processes or pathways.
[79]
[PDF] Chemical control of spider mites
What Acaricides Should/Can I Apply? • Several active ingredients available. • Some have insecticidal and acaricidal properties. • Factors to consider before ...Missing: types | Show results with:types
[80]
[PDF] Two spotted spider mite on hop - Michigan State University
By mid-July, the threshold increases to 5-10 mites/leaf. It is un- clear at this time how applicable these thresholds are in Michigan. Figure A. Symptoms of ...
[81]
A link between host plant adaptation and pesticide resistance ... - NIH
T. urticae is an extreme polyphagous pest with more than 1,100 documented hosts and has an extraordinary ability to develop pesticide resistance. When mites ...
[82]
[PDF] W 415 The Insecticide and Miticide Mode of Action Field Guide
Currently, clofentezine, etoxazole and hezythiazox are available for control of spider mites in indoor and/or outdoor areas. Page 29. endorsement, or ...
[83]
Spider Mites / Home and Landscape / UC Statewide IPM Program ...
Spider mites prefer hot, dusty conditions and usually are first found on trees or plants adjacent to dusty roadways or at margins of gardens.Management · Biological Control · Chemical Control
[84]
Two-spotted Spider Mite | Cooperative Extension
Development is faster the hotter it is; complete in 5 days when temperatures are over 90 degrees Fahrenheit.Damage · Natural Enemies · Chemical Control
[85]
Spider Mite Herbivores Thrive in Drought - Learn Genetics Utah
Spider mites are one of these herbivores. These pests damage crops during drought conditions and make crop losses worse.
[86]
Twospotted Spider Mites : Greenhouse & Floriculture - UMass Amherst
The larval stage is followed by two nymphal stages (a protonymph and a deutonymph) and by the adult stage. The nymphal and adult stages have four pairs of legs.Twospotted Spider Mite... · Description And Life Cycle · Biological Control (from New...
[87]
Integrated Pest Management (I.P.M.) for Spider Mites - Clemson HGIC
Nov 20, 2017 · When examining plants, it is best to take a white sheet of paper and tap the leaf several times with the hand, examine the paper for creatures ...
[88]
[PDF] Spider Mite Control - Atticus LLC
Cultural: remove weeds that can provide an alternate host site; reduce drought stress by providing adequate and even irrigation; avoid overapplication of ...
[89]
Improved resistance to disease and mites in strawberry, through the ...
May 4, 2016 · The application of harpin protein also caused a reduction in mite damage, while increasing photosynthetic rate and the production of marketable ...
[90]
Influence of Soybean Lines Isogenic for Pubescence Type on ...
Results suggest that leaf pubescence, or in this case lack of, could be a potential factor in the control of the twospotted spider mite on soybean.
[91]
Scouting and Biological Control of Two-spotted Spider Mite
Jun 3, 2005 · It is also a pest notorious for developing resistance to traditional miticides. Spider mites are tiny but have the ability to increase quickly.
[92]
Scouting for Bugs; They are not all Thugs - Blogs - University of Florida
Sep 27, 2018 · Stick tapes are effective for scale crawlers and spider mites. When scouting, it is important to pay close attention to the underside of leaves.<|control11|><|separator|>