Mites (Acari) threaten ex situ conservation actions of Ipomoea cavalcantei D.F. Austin (Convolvulaceae), an endemic species from Carajás National Forest, Pará, Brazil

Ipomoea cavalcantei D.F. Austin (Convolvulaceae) is a Highly Restricted Endemic species only found in Canga vegetation in conservation areas in the Carajás region, Parauapebas, State of Pará, in the Brazilian Amazon. Due to edaphic endemism and the increase in mineral exploration in the Carajás, it is necessary to cultivate I. cavalcantei outside of its habitat in order to preserve the species. On plants cultivated in a greenhouse covered with shade, at the Parauapebas Campus of the Universidade Federal Rural da Amazônia (UFRA), symptoms of pest attack were observed. The aim of this study was to characterize the damage and confirm the identification of the mite species causing injuries to the leaves of I. cavalcantei when cultivated outside its natural environment. The leaves of the plant had light green spots, which initially appeared as small dots. As the symptoms intensified, these spots coalesced, evolving into larger, yellowish spots, later necrosis and leaf fall at the slightest mechanical action. Mites were found on the abaxial surface of leaves, in abundant colonies, surrounded by a dense layer of webs, used for dispersion and oviposition of mites. This behavior, added to the shape of the eggs (spherical and hyaline) is characteristics of the mites of the genus Tetranychus Dufour, 1832 (Acari: Tetranychidae). Some female and male specimens were preserved for later identification. This is the first occurrence of Tetranychus ludeni Zacher, 1913 on I. cavalcantei and represents an important issue for conservation programs aimed at protecting I. cavalcantei

Two new species of Tydeidae (Acari: Prostigmata), records of species of this family and Triophtydeidae from Brazil

ABSTRACT Two new species of Tydeidae are described, Brachytydeus lorenzatus sp. nov. and Quasitydeus feresi sp. nov. Brachytydeus lorenzatus sp. nov. differs from B. aegyptiaca (Rasmy & El Bagoury, 1979) by having a reticulated area on the region of f1 and f2 , dorsal setae smooth, solenidion (I shorter than or equal to the width of tarsus I, most setae on dorsal shield shorter than the length between their bases and setae d forked distally. The new species is distinguished from B. scutatus Silva, Rocha & Ferla, 2013 by having a slightly reticulate area on the aspidosoma, near setae bo , all dorsal setae slender and club-shaped. Quasitydeus feresi sp. nov. differs from the only other species of the genus, Q. ricensis (Baker, 1970), by having all dorsal setae simple and serrated, similar in shape. Eleven tydeoid species are reported also from several plants native to the state of Rio Grande do Sul, Brazil. This is the second species of Brachytydeus Thor, 1931 described from and the second species described for Quasitydeus Kaźmierski, 1996

Intercropped Plants Provide a Reservoir of Predatory Mites in Coffee Crop

Conservation biological control of pests may be achieved using a variety of integrated strategies based on crop diversification. We investigated whether the insertion of the intercropped plants species (IPS) Inga edulis, Senna macranthera, and Varronia curassavica modified the abundance of mites, their feeding behavior, and the dissimilarity of predator and herbivore mites over a gradient of distance from the IPS on coffee. To accomplish this, we recorded the mite species on coffee plants along transects of 16 m extending from the IPS, including on the IPS. A total of 8946 specimens were sampled. Tenuipalpidae was the most abundant family on coffee, followed by Tydeidae, while Eriophyidae was the most abundant on the IPS, followed by Phytoseiidae. The abundance and richness of mites differed between their feeding behavior and distance. The dissimilarity of predators and herbivores increased along a gradient of distance. Furthermore, the IPS harbored several mite species and the diversity of predator and herbivore mites among the IPS was different. The findings suggest that the intercropped plant species can attract and serve as a reservoir of predatory mites on coffee crops, which could improve the biocontrol of pest mites on coffee

Intercropped Plants Provide a Reservoir of Predatory Mites in Coffee Crop

Conservation biological control of pests may be achieved using a variety of integrated strategies based on crop diversification. We investigated whether the insertion of the intercropped plants species (IPS) Inga edulis, Senna macranthera, and Varronia curassavica modified the abundance of mites, their feeding behavior, and the dissimilarity of predator and herbivore mites over a gradient of distance from the IPS on coffee. To accomplish this, we recorded the mite species on coffee plants along transects of 16 m extending from the IPS, including on the IPS. A total of 8946 specimens were sampled. Tenuipalpidae was the most abundant family on coffee, followed by Tydeidae, while Eriophyidae was the most abundant on the IPS, followed by Phytoseiidae. The abundance and richness of mites differed between their feeding behavior and distance. The dissimilarity of predators and herbivores increased along a gradient of distance. Furthermore, the IPS harbored several mite species and the diversity of predator and herbivore mites among the IPS was different. The findings suggest that the intercropped plant species can attract and serve as a reservoir of predatory mites on coffee crops, which could improve the biocontrol of pest mites on coffee

Distribuição espacial e plano de amostragem de Calacarus heveae (Acari) em seringueira Spatial distribution and sampling plan for Calacarus heveae (Acari) on rubber trees

Calacarus heveae Feres, 1992 é um eriofídeo descrito de espécimes coletados em plantas de seringueira (Hevea brasiliensis, Euphorbiaceae) na região noroeste do Estado de São Paulo. Esse ácaro prefere a face adaxial dos folíolos e pode causar a perda do brilho, amarelecimento, bronzeamento dessa região e a subseqüente queda prematura das folhas. O objetivo deste trabalho foi analisar a distribuição de C. heveae em seringueira, selecionar a unidade de amostragem mais representativa e desenvolver um plano de amostragem para o estudo de sua flutuação populacional. O trabalho foi conduzido com os clones PB 260 e IAN 873, respectivamente nos municípios de Itiquira e de Pontes e Lacerda, ambos no Mato Grosso. Em Itiquira, diferenças significativas foram observadas em quatro ocasiões em relação ao número médio de ácaros por folha nos diferentes estratos das plantas. Nas amostragens realizadas em Pontes e Lacerda, nenhuma diferença significativa foi encontrada entre os estratos em relação àquele parâmetro. Apenas em Itiquira, em uma ocasião de amostragem, foi verificada diferença entre os três estratos, em relação à proporção de folhas infestadas. Nenhuma diferença significativa foi verificada em relação ao número médio de ácaros por folha e proporção de folhas infestadas por C. heveae a diferentes distâncias da periferia da copa. Calacarus heveae exibe distribuição agregada no campo. Para estimar a densidade de C. heveae, um plano numérico e um plano binomial de amostragem foram desenvolvidos.<br>Calacarus heveae Feres, 1992 (Eriophyidae) is a mite described from specimens collected on rubber tree (Hevea brasiliensis, Euphorbiaceae) in the northwest region of the state of São Paulo. This mite prefers the adaxial face of the folioles which it can turn dry, yellowish and brownish; it can also cause leaf fall. The aim of this work was to analyze the distribution of C. heveae on rubber trees, to select the most representative sampling unit and to develop a sampling plan to determine the populational fluctuation. This study was conducted with clones PB 260 and IAN 873, in Itiquira and Pontes e Lacerda, respectively, both in the state of Mato Grosso. In Itiquira, significant differences were observed in four occasions in relation to the average number of mites per leaf in the different plant strata. In the samplings carried out in Pontes e Lacerda, no significant differences were observed between strata in relation to that parameter. Only in Itiquira, in one occasion, a significant difference between strata was verified in relation to the proportion of infested leaves. No significant differences were verified in relation to the average number of mites per leaf and proportion of leaves infested by C. heveae at different depths in the canopy. Calacarus heveae exhibits aggregated distribution in the field. To estimate the density of C. heveae, numeric and sampling plans were developed

Flutuação populacional e sintomas de dano por ácaros (Acari) em seringueira no Estado do Mato Grosso, Brasil Population fluctuation and mite (Acari) damage symptoms in rubber trees in the State of Mato Grosso, Brazil

Apesar da grande importância da cultura da seringueira (Hevea brasiliensis Muell. Arg.) para o Brasil, pouco se conhece sobre a flutuação populacional dos ácaros nessa cultura. O objetivo deste trabalho foi estudar a flutuação populacional de ácaros na seringueira no Estado do Mato Grosso, bem como observar a evolução dos sintomas de ataque de tais pragas nessa planta. O estudo foi conduzido em campos de seringueira de Itiquira e Pontes e Lacerda, Estado do Mato Grosso, com seis clones: FX 3864, RRIM 600, IAN 873, IAN 713, PB 260 e PR 255, cujas coletas foram realizadas de agosto de 1998 a julho de 2000. Na safra de 1998/1999, a amostragem foi de 150 folhas de cada um dos estratos basal, mediano e apical, em 10 plantas ao acaso. A metodologia de coleta na safra de 1999/2000 foi alterada devido aos resultados da parcial anterior de cinco folhas do estrato mediano de cada uma das 15 plantas ao acaso. Calacarus heveae Feres foi a espécie mais freqüente em Itiquira e Phyllocoptruta serigueirae Feres em Pontes e Lacerda. A queda prematura das folhas foi observada apenas em Itiquira.<br>Despite the importance of rubber trees (Hevea brasiliensis Muell. Arg.) to Brazil, little is known about mite population fluctuation on this crop. The aim of this work was to study the fluctuation of the mite population on rubber trees in the state of Mato Grosso and to observe the evolution of the symptoms caused by their attack. This study was conducted in rubber tree fields at Itiquira and Pontes e Lacerda in the state of Mato Grosso with six clones: FX 3864, RRIM 600, IAN 873, IAN 713, PB 260 and PR 255. Samplings were conducted between August 1998 and July 2000. The 1998/1999 samples consisted of 150 leaves of each of the basal, median and apical strata of 10 plants, randomly taken. The 1999/2000 sampling methodology was changed due the results for the previous partial for five leaves of the median stratum of each of 15 plants randomly taken. Calacarus heveae Feres was the most frequent species in Itiquira and Phyllocoptruta serigueirae Feres in Pontes e Lacerda. Early leaf drop was observed only in Itiquir