Flat Mite Research Articles

The invasive flat mite, Brevipalpus californicus (Banks, 1904) in Hungary: Notes to the morphology, new locality and new host

Three specimens of invasive pest mite, Brevipalpus californicus (Banks, 1904) were collected on leaves of Dracaena marginata ʻTricolorʼ plant. The collected specimens belong to the Beard et al. (2015) “species B group” on the basis of the morphology of prodorsal and opisthonothal pattern. A new key to the Hungarian Brevipalpus is given.

Two species of Acaricis (Acari: Tenuipalpidae) from New Zealand, moved from the genus Tenuipalpus, with a key to the known species

Acaricis Beard and Gerson (Acari: Tenuipalpidae) is a small genus of flat mites with three species described from Australian and New Zealand sedges (Poales: Cyperaceae). In this article, we redescribe two species, Tenuipalpus montanus Collyer and T. alpinus Collyer, and move them to the genus Acaricis, so that these species become Acaricis montanus (Collyer) comb. nov. and A. alpinus (Collyer) comb. nov.. These two species share several characters with other Acaricis that species of Tenuipalpus do not. A key to the world species of Acaricis is also proposed.

A new species of Aegyptobia and redescription of Tenuipalpusszarvasensis Bozai, 1970 (Acari, Tenuipalpidae).

A new tenuipalpid mite species, Aegyptobiabozaiisp. n., is described from Central-Hungary on leaves of the endemic Hungarian statice Limoniumgmeliniisubsp.hungaricum (Plumbaginaceae) based on females, nymphs and larva. The previously described endemic flat mite, Tenuipalpusszarvasensis Bozai, 1970 is redescribed. This species had been treated as a junior synonym of Tenuipalpuscheladzeae Gomelauri, 1960, but our new investigation shows that the two species are not the same.

Identification and Characterization of Citrus Chlorotic Spot Virus, a New Dichorhavirus Associated with Citrus Leprosis-Like Symptoms.

Local chlorotic spots resembling early lesions characteristic of citrus leprosis (CL) were observed in leaves of two sweet orange (Citrus sinensis L.) trees in Teresina, State of Piauí, Brazil, in early 2017. However, despite the similarities, these spots were generally larger than those of a typical CL and showed rare or no necrosis symptoms. In symptomatic tissues, transmission electron microscopy revealed the presence of viroplasms in the nuclei of the infected parenchymal cells and rod-shaped particles with an average size of approximately 40 × 100 nm, resembling those typically observed during infection by dichorhaviruses. A bipartite genome of the putative novel virus, tentatively named citrus chlorotic spot virus (CiCSV) (RNA1 = 6,518 nucleotides [nt] and RNA2 = 5,987 nt), revealed the highest nucleotide sequence identity values with the dichorhaviruses coffee ringspot virus strain Lavras (73.8%), citrus leprosis virus N strain Ibi1 (58.6%), and orchid fleck virus strain So (56.9%). In addition to citrus, CiCSV was also found in local chlorotic lesions on leaves of the ornamental plant beach hibiscus (Talipariti tiliaceum (L.) Fryxell). Morphological characterization of mites recovered from the infected plants revealed at least two different types of Brevipalpus. One of them corresponds to Brevipalpus yothersi. The other is slightly different from B. yothersi mites but comprises traits that possibly place it as another species. A mix of the two mite types collected on beach hibiscus successfully transmitted CiCSV to arabidopsis plants but additional work is required to verify whether both types of flat mite may act as viral vectors. The current study reveals a newly described dichorhavirus associated with a citrus disease in the northeastern region of Brazil.

Parámetros de transmisión del virus de la leprosis de los cítricos por Brevipalpus yothersi (Acari: Tenuipalpidae)

La leprosis de los cítricos, causada por virus (Citrus Leprosis Virus, CiLV), es un problema fitosanitario de importancia económica y cuarentenaria para la citricultura de países productores. En Colombia su presencia fue confirmada en 2004 en los departamentos del Meta y Casanare; el ácaro Brevipalpus yothersi Baker (antes identificado como Brevipalpus phoenicis Geijskes) (Acari: Tenuipalpidae), se reconoce como el principal vector del virus en el país. Se determinaron los parámetros: período de acceso para adquisición, período de acceso para inoculación y porcentaje de ácaros infectados con CiLV, por medio de pruebas de transmisión y análisis moleculares en el Centro de Investigación “La Libertad” de CORPOICA, Meta, Colombia. Al probar períodos de adquisición entre 10 minutos y 72 horas, se encontró que B. yothersi adquiere el virus después de 30 minutos de alimentación sobre hojas de naranja Valencia (Citrus sinensis L.) Osbeck con lesiones de leprosis. El período mínimo requerido por los ácaros para transmitir el virus hacia plantas de C. sinensis fue de 10 minutos. Para períodos de transmisión desde 10 minutos hasta 24 horas, los porcentajes de infección variaron entre 25 y 68,75 % en las hojas receptoras. De acuerdo a pruebas de transmisión y análisis RT-PCR, después de tres días de alimentación sobre lesiones de leprosis, el 40 % de las poblaciones del ácaro evaluadas adquirió el virus CiLV-C2. Los resultados obtenidos amplían el conocimiento de las interacciones planta - virus - vector, lo cual es fundamental para el establecimiento de programas de prevención y manejo de la enfermedad.

Flat Mites: A Potential Threat to Turfgrasses Worldwide, or Already Widespread?

Two species of flat mites (Acari: Tenuipalpidae) from the genus Dolichotetranychus have recently been found to cause significant damage to Cynodon (bermudagrass) and Zoysia spp. turfgrasses. Despite records of D. australianus infesting bermudagrass throughout Africa, the Middle East, and Australia for more than 70 yr, most turf managers assume that any apparent mite damage is due to the widely publicized eriophyoid bermudagrass mite, Aceria cynodoniensis, rather than validating this under the microscope. To an experienced eye, the visual symptoms are distinctly different from those typically associated with A. cynodoniensis; but they are similar to the symptoms seen with the zoysiagrass mite, D. zoysiae, in Okinawa (Japan). The possibility that there may be further undescribed or misidentified Dolichotetranychus species affecting turfgrasses is discussed, together with examples and biosecurity implications. One such species that may prove to be more significant than hitherto suspected, if routine microscopic diagnosis were to be implemented, is D. summersi, which has been recorded five times from bermudagrass in the United States during the 1950s and 1960s but without any indication of the symptoms caused. The importance of making microscopic examinations of suspected mite infestations is emphasized.

A review of Ultratenuipalpus (Trombidiformes: Tenuipalpidae) and related genera, with a new species from forest oak Allocasuarina torulosa (Aiton) (Casuarinaceae)

ABSTRACTA new species of flat mite (Acari: Tenuipalpidae), Ultratenuipalpus jubatus Otley, Beard and Seeman sp. nov., is described from the green stems of forest oak Allocasuarina torulosa (Aiton) L.A.S. Johnson (Casuarinaceae) in Australia. We reinstate Extenuipalpus as a genus, with E. quadrisetosus (Lawrence, 1940) as the type species, and move Tenuipalpus niekerkae Meyer, 1979 and Tenuipalpus saggitus Meyer, 1993a to Extenuipalpus. We treat Urigersonus as a junior subjective synonym of Ultratenuipalpus, thus returning Urigersonus bunyai (Smiley and Gerson, 1995) to Ultratenuipalpus. The genera Ultratenuipalpus and Extenuipalpus are diagnosed and a key is provided for each genus. Ultratenuipalpus is shown to comprise two groups that generally conform to a biogeographic pattern: those species without seta f2 show a Gondwanan distribution, post-separation from Africa, while those with seta f2 are found in Africa, North America and East Asia. We also show that the pair of pseudanal setae that are modified into genital stylets in the male are setae ps3, not ps1 as previously thought, and therefore setae ps3 are always present in flat mites.

Morphological and genetic characteristics of Brevipalpus lewisi (Acari: Tenuipalpidae) and comparison with other three Brevipalpus species

ABSTRACTThe flat mite, Brevipalpus lewisi McGregor was recently found infesting Metasequoia glyptostroboides Hu & Cheng (Taxodiaceae) in China. In order to accurately differentiate this species from other closely related Brevipalpus species and appropriately apply prevention and control strategies, this study focused on morphological description and identification of adults based on electron microscopy and molecular sequencing of the mitochondrial cytochrome oxidase subunit I gene. Morphological analyses showed significant differences and similarities between B. lewisi (McGregor), Brevipalpus phoenicis (Geijskes), Brevipalpus californicus (Banks) and Brevipalpus obovatus Donnadieu in the number and/or quality of dorsal setae, omega on tarsus II, dorsal cuticular patterns and leg chaetotaxy. Phylogenetic analyses of mitochondrial CO I gene fragment (342 bp) indicated B. lewisi is 86% homologous with the other three species. The genetic distance between B. lewisi host-associated populations of M. glyptostroboides and Vitis vinifera (Vitaceae) is 6.7%, suggesting the existence of genetic divergence between hosts.

SPATIAL DISTRIBUTION AND SEQUENTIAL SAMPLING OF Brevipalpus phoenicis IN CITRUS

ABSTRACT Among the pests of citrus, one of the most important is the red and black flat mite Brevipalpus phoenicis (Geijskes), which transmits the Citrus leprosis virus C (CiLV-C).When a rational pest control plan is adopted, it is important to determine the correct timing for carrying out the control plan. Making this decision demands constant follow-up of the culture through periodic sampling where knowledge about the spatial distribution of the pest is a fundamental part to improve sampling and control decisions. The objective of this work was to study the spatial distribution pattern and build a sequential sampling plan for the pest. The data used were gathered from two blocks of Valencia sweet orange on a farm in São Paulo State, Brazil, by 40 inspectors trained for the data collection. The following aggregation indices were calculated: variance/ mean ratio, Morisita index, Green’s coefficient, and k parameter of the negative binomial distribution. The data were tested for fit with Poisson and negative binomial distributions using the chi-square goodness of fit test. The sequential sampling was developed using Wald’s Sequential Probability Ratio Test and validated through simulations. We concluded that the spatial distribution of B. phoenicis is aggregated, its behavior best fitted to the negative binomial distribution and we built and validated a sequential sampling plan for control decision-making.

EFICIÊNCIA DE ACARICIDAS SOBRE POPULAÇÕES DE Brevipalpus phoenicis (GEIJSKES) (ACARI: TENUIPALPIDAE) DE CITROS E CAFEEIRO

EFICIÊNCIA DE ACARICIDAS SOBRE POPULAÇÕES DE Brevipalpus phoenicis (GEIJSKES) (ACARI: TENUIPALPIDAE) DE CITROS E CAFEEIRO

Tenuipalpidae (Acari: Trombidiformes) from Casuarinaceae (Fagales).

The Tenuipalpidae associated with the Casuarinaceae are reviewed, including one new genus, Palpipalpus gen. nov., twelve new species, and seven redescriptions. Two new generic records for Australia are established, Pentamerismus and Philippipalpus. The new species are: Chaudhripalpus costacola Beard and Seeman sp. nov., Crossipalpus gersoni Beard and Seeman sp. nov., Crossipalpus raveni Beard and Seeman sp. nov., Magdalenapalpus caperatus Beard and Seeman sp. nov., Magdalenapalpus forsteri Seeman and Beard sp. nov., Pentamerismus sititoris Beard and Seeman sp. nov., Pentamerismus hicklingorum Seeman and Beard sp. nov., Pentamerismus wardo Seeman and Beard sp. nov., Palpipalpus hesperius Beard and Seeman sp. nov. gen. nov., Philippipalpus flumaquercus Beard and Seeman sp. nov., Philippipalpus belah Beard and Seeman sp. nov., and Philippipalpus nigraquercus Seeman and Beard sp. nov. Meyeraepalpus delfinadae Smiley et al., is reinstated based on new material and an analysis of its phylogenetic relationships. Crossipalpus muellerianae Smiley et al., Crossipalpus verticillatae Smiley et al., and Tegopalpus conicus Womersley are redescribed and rediagnosed from the original type specimens and newly collected material; and Chaudhripalpus creelae (Smiley et al.), Magdalenapalpus strandtmanni (Smiley et al.) and Philippipalpus agohoi Corpuz-Raros are redescribed and rediagnosed from type material only. All flat mite species were host-specific. Up to three species of flat mite were collected from a single she-oak species. Leg setation and ontogeny are reviewed for the taxa studied. A key to Tenuipalpidae from Casuarinaceae is provided. A phylogeny of the subfamily Tegopalpinae found the following relationships: Meyeraepalpus (Australopalpus, Crossipalpus, Palpipalpus (Magdalenapalpus (Philippipalpus (Chaudhripalpus + Tegopalpus)))). Our preliminary analysis of the Tegopalpinae suggested the group is monophyletic and its sister group is Phytoptipalpus.

ブドウにおけるブドウヒメハダニの発生状況と薬剤殺虫効果

ブドウにおけるブドウヒメハダニの発生状況と薬剤殺虫効果

Types of Brevipalpus californicus (Banks) (Tenuipalpidae) in Egypt

A survey of Brevipalpus californicus (Banks) infesting fruit orchards was conducted in all Egyptian provinces to discover the different types of B. californicus in Egypt. Samples were collected from plant foliages, fruits, buds and branches. The study disclosed on presence of two types of the flat mite, B. californicus, as first record in Egypt, and the differences between both of them were discussed.

Cryptic diversity in Brevipalpus mites (Tenuipalpidae)

Defining the taxonomic identity of organisms is a prerequisite for their study, and in the case of economically important species, misidentification may lead to the application of inappropriate prevention and control strategies. Flat mites of the Brevipalpus genus include several crop pests and the systematics of these mites represents a challenge for acarologists. Many of the most economically important Brevipalpus species have repeatedly been inaccurately identified. Such problematic classification has been attributed to the likely occurrence of cryptic species in the genus. In this study, we used an integrative approach that combined molecular analyses, including sequence‐based species delimitation, with detailed morphological identification using traits that have recently showed to be taxonomically informative. Sequences of mitochondrial cytochrome c oxidase subunit I (COI) were obtained from individuals collected from host plants belonging to 14 genera and 13 families across 29 locations in the Americas (Brazil, Chile, USA). The phylogenetic analyses included previously published Brevipalpus sequences from GenBank, and the final data set was classified into 44 haplotypes. Six putative species were recognised by COI‐based species delimitation analysis, and morphological evidence supported each of these species. The integrative approach revealed the occurrence of cryptic species in the Brevipalpus genus and contributed to the clarification of previously noted incongruences. The results presented here allow for the evaluation of taxonomic characteristics in a phylogenetic context and indicate new characters for the differentiation of Brevipalpus species. In addition, Brevipalpus incognitus n. sp. Ferragut & Navia, a cryptic species detected in this study, is described based on morphological and molecular traits. Implications of the advances in Brevipalpus systematics presented herein with respect to pest management are briefly discussed.

Accelerating biodiversity descriptions and transforming taxonomic publishing: the first decade of Zootaxa

Zootaxa was launched ten years to help taxonomists overcome the taxonomic impediment by enabling them to describe biodiversity in a rapid and efficient way. The first paper on a new species of flat mite (Acari: Tenuipalpidae) was published in Zootaxa 1 on 28 May 2001 (Moraes & Freire 2001). Unlike many regularly-scheduled journals, each paper in Zootaxa was separately issued and published without delay after acceptance by the editor, and there are no page charges or a small fee to support open access. In addition, Zootaxa offers the flexibility to publish manuscripts of any length, so long as they pass peer review. Many colleagues were excited and encouraged by the prospects of such a brand new journal and some of them joined as associate editors to facilitate rapid processing of manuscripts. The journal has met the needs of authors and sustained an early phase of very rapid growth (Figs 1–3), with issue/paper 1,000 published on 27 May 2005 (Rodiles-Hernández et al. 2005). In the first four years, over 1,100 authors from all over the world published 23,000 pages in Zootaxa (Zhang 2005). Thereafter, short papers of fewer than 60 pages were no longer issued separately because several papers were often published on the same day; instead, short papers were grouped to form standard issues of 60, 64, or 68 pages to save paper, printing and mailing costs, with relatively little effect on the speed of publication.

COMMERCIAL POMEGRANATE (PUNICA GRANATUM L.) PRODUCTION IN CALIFORNIA

Commercial pomegranate production in California is found primarily in the southern San Joaquin Valley, a region with Mediterranean type climate. Pome-granates have been grown in California since 1792, spread by Christian missionaries from Spain, and in commercial production since 1896 when shipments of trees arrived from Florida. For decades in the late 1900s the statewide hectarage remained near 1000, but has increased dramatically to 11700 in 2007, most of which is less than four years old. Pomegranates are often grown in conjunction with other permanent crops such as stone fruit and nut crops. Planting systems range from rows 3.6 to 5.8 m and in-row spacing from 1.5 to 5.2 m, with row spacing often determined by equipment preferences for other crops. Training systems are typically free-form multiple trunks, although single trunk and trellised production is being used. Irrigation systems, like crop spacing, are often dictated by companion crops found on individual farms; flood irrigation is found on older trees with newer trees planted with micro irrigation systems. Organic production of pomegranates remains limited due to market acceptance; challenges for organic production are Alternaria alternata and Aspergillus niger, as well as omnivorous leafroller (Platynota stultana) and flat mite (Brevipalpus lewisi). Numerous herbicides are registered for use in conventional pomegranates and weed barriers and hand weeding in organic systems. Both fresh market and juice fruit continue to be commercially harvested by hand but attempts at mechanization for both uses are underway. Common yields for mature pomegranates are as low as 6-10 MT/ha when used exclusively for fresh market consumption, but can be as great as 25-35 MT/ha when grown for juice, with the fresh:juice ratio dependant on both market conditions and autumn weather patterns. Most pomegranates are sold through food retailers in North America, and their current preference for high sugar/high acid, dark red rind color and dark red aril color favors cultivars such as ‘Granada’ and ‘Foothill’ in early season, and ‘Wonderful’ in main season. The United States Depart-ment of Agriculture National Clonal Germplasm Repository in Davis, California, contains selected lines sent from Dr. Levin’s Turkmenistan collection as well as genetic variants found in California production; variation for fruit attributes may influence consumer acceptance to other fruit types already common throughout pomegranate consuming cultures.

Herbivore Exploits Chink in Armor of Host

Knowledge of plant-feeding mite diversity, their interactions with host plants, and their ecological impact are not clear or have been too narrowly studied in the past. The mite superfamily Tetranychoidea has been identified around the world feeding on almost every plant known. Spider mites (Tetranychidae) are the most common mite recognized by farmers, researchers, and any person with an ornamental plant at home. On the other hand, flat mites (Tenuipalpidae) are also common on plants, but are often overlooked due to their small size and camouflaging colors. Mites in the flat mite genus Raoiella Hirst are obligate plant parasites that feed via stylet-like mouthparts adapted to pierce plant tissues. A species of particular interest in this genus, the red palm mite, R. indica Hirst, is currently spreading aggressively throughout the Americas on species of palm (Arecaceae). How they feed on the plant and how they are able to multiply into huge populations on one host plant have only recently been studied. Here, using low-temperature scanning electron microscopy. R. indica and several other species in this genus were captured and observed for the first time feeding via the stomatal aperture of host plants in several different families. These findings on their different host plants challenged our common belief that all plant-feeding mites feed by piercing the epidermis. Stomatal feeding could negatively affect the plant's ability to regulate gas and water exchange. Further examination of feeding methods for other herbivorous mites is necessary.

Silwet L-77 Improves the Efficacy of Horticultral Oils for Control of Boisduval ScaleDiaspis boisduvalii(Hemiptera: Diaspididae) and the Flat MiteTenuipalpus pacificus(Arachnida: Acari: Tenuipalpidae) on Orchids

Pest management of insects and mites on orchids has been based on the use of synthetic organic pesticides. However, less-toxic chemical control is needed by hobbyists and small growers. Orchids from 8 genera were treated with Silwet L-77 alone and no evidence of phytotoxicity was seen. Subsequently, 3 petroleum oils in combination with Silwet L-77 were tested to determine efficacy in suppressing Boisduval scale Diaspis boisduvalii Signoret (Hemiptera: Diaspididae) and the flat mite Tenuipalpus pacificus Baker (Arachnida: Acari: Tenuipalpidae). The results indicate Silwet L-77 increased toxicity of the oils and increased removal of the scales and mites from foliage over oil alone, yet no phytotoxicity was observed in any of the plants treated. Petroleum oil Silwet L-77 is considered low-toxic, may be less expensive than some pesticides, and may conserve natural enemies, making it a potential addition to an integrated pest management program for orchids.

A review of a new catalog and illustrated key to facilitate identification of and research on flat mites (Acariformes: Tenuipalpidae)

The flat mites, also known as the false spider mites, are one of the most diverse groups of plant feeding mites (Prostigmata: Tetranychoidea: Tenuipalpidae). There has been increasing interests in the Tenuipalpidae both from applied and fundamental perspectives (Gerson 2008). The applied interest is to a large extent caused by roles of Brevipalpus species in vectoring the leprosis virus resulting in the widespread epidemic in the Americas (Childers et al. 2003) and also the recent introduction of invasive mites such as Raoiella indica Hirst to the Americas (Flechtmann & Etienne 2004). Also there has been recent interest in using tenuipalpid mites as model organisms to explore basic evolutionary questions such as sex determination and microorganism-mite interactions (Gerson 2008). There is a great need for an updated and comprehensive guide to the taxonomy of the family. The recent book by Mesa et al. (2009) is the first step towards fulfilling that need.

Population dynamics of Aceria guerreronis Keifer (Acari: Eriophyidae) and associated predators on coconut fruits in Northeastern Brazil

Aceria guerreronis Keifer can cause severe damage to coconuts in several countries around the world. Rare studies have been conducted to determine the predatory mites associated with A. guerreronis in Brazil. The study evaluated the prevalence of A. guerreronis and associated predators on the bracts and on the surface of the fruits underneath the bracts, for 12 months, on coconut palms grown along the coast of the States of Alagoas, Paraíba and Pernambuco, Northeastern Brazil. Mites of 10 families were found, but by far the most abundant species was A. guerreronis, corresponding to 99.5% of the mites collected. The prevailing species amongst the predators were the Phytoseiidae mites Neoseiulus baraki (Athias-Henriot) and Neoseiulus paspalivorus (De Leon). These are flat mites that have short limbs, characteristics that allow them to invade the main habitat occupied by A. guerreronis. Other predators were found, but in low numbers, due mainly to their difficulty in reaching the fruit areas most inhabited by A. guerreronis. However, these mites could prey on that pest when it leaves its preferred habitat to disperse. No significant correlations were observed between the levels of abiotic factors and the population levels of A. guerreronis or of the phytoseiids associated with it. This probably occurred due to the simultaneous and conflicting effects of those factors on the mites in the field, or to significant differences between the climatic factors measured in the environment and those prevailing in the habitat occupied by A. guerreronis.