Effect of air humidity on the egg viability of predatory mites (Acari: Phytoseiidae, Stigmaeidae) common on rubber trees in Brazil

Rubber pest mites, Calacarus heveae and Tenuipalpus heveae, reach economic damage levels at the end of the rainy season and the beginning of the dry season in Brazil. Therefore, low humidity adaptation might be an important characteristic for predatory mites to successfully control pest organisms. This study determined the effect of the relative humidity (RH) levels of 30-100% on the hatching of larvae of Amblyseius acalyphus, Euseius citrifolius, Iphiseiodes zuluagai, Metaseiulus camelliae, Agistemus floridanus and Zetzellia malvinae at 25 ± 0.5°C. These predatory mites are common on rubber trees in the state of São Paulo and might be used for introduction in the major rubber tree production regions in the state of Mato Grosso. At 70% RH or higher, viability was 70% or higher for all species, indicating that their performance might be higher during the rainy season than during the dry season. Eggs of E. citrifolius and M. camelliae presented higher viability at the lower relative humidity levels than those of other species, indicating that these species might have higher chance to persist in the dry season. It is suggested that M. camelliae should be further evaluated for introduction in the state of Mato Grosso, considering that this mite is not yet present in that area. © Springer 2006.

Three new species of Tenuipalpus Donnadieu (Acari, Tenuipalpidae) from the State of São Paulo, Brazil

Three new species of Tenuipalpus, T. carlosflechtmanni n. sp., T. moraesi n. sp. and T. ariauae n. sp., collected on wild plants in Brazil, are described and illustrated. Copyright © 2006 Magnolia Press.

Tetrabdella neotropica (Acari: Bdellidae), a new genus and species from Brazil

Tetrabdella neotropica Hernandes & Feres n. gen., n. sp. is the first representative of the family Bdellidae from South America. It can be distinguished from other bdellid mites by the presence of two trichobothriae on tarsi III and IV. The subfamily Spinibdellinae is herein redefined to accomodate the new genus. A key to world genera of Bdellidae is presented. Copyright © 2006 Magnolia Press.

A new species of Typhlodromus Scheuten (Acari: Phytoseiidae) from Brazil

A new species of phytoseiid mites is described from Brazil, Typhlodromus moraesi sp. nov., collected on Tabebuia alba (Cham.) Sandwith and Chamaesyce hirta (L.) Millsp. in the State of São Paulo. This is the second species of the T. arizonicus group. Copyright © 2006 Magnolia Press.

Two new species of the feather mite subfamily Pterodectinae (Acari: Astigmata: Proctophyllodidae) from Brazil

We describe two new pterodectine feather mites (Analgoidea: Proctophyllodidae) from Brazilian passerines (Passeriformes): Pterodectes amaurochalinus sp. n., from Turdus amaurochalinus Cabanis (Turdidae), and Dolichodectes neotropicus sp. n., collected from Elaenia chiriquensis Lawrence (Tyrannidae). A key to species of the genus Dolichodectes is presented. Copyright © 2006 Magnolia Press.

Seletividade de alguns agrotóxicos em uso na citricultura ao ácaro predador Neoseiulus californicus (McGregor) (Acari: Phytoseiidae)

This work was carried out to determine the residual toxicity of the main pesticides used in citrus, on Neoseiulus californicus (McGregor) under laboratory conditions. For this, it was used the residual contact bioassay. Citrus leaves of the variety Pêra were sprayed in a Potter tower. The residual action was evaluated at 2 hours and 1; 3; 5; 7; 10; 14 e 21 days after treatment. Ten adult females of N. californicus were transferred to each ring, together with an enough amount of Tetranychus urticae nymphs and adults to feed the predator. Mortality evaluations were performed at 72 hours after treatment. Bioassays indicate that the pesticides: acrinathrin, deltamethrin, dinocap, sulphur, fenpropathrin, fenbutatin oxide and propargite were innocuous to N. californicus. On the other hand, abamectin, azocyclotin e cyhexatin caused mortalities of 29.8; 32.0 e 34.1%, respectively, two hours after transference. Dicofol, pyridaben and chlorfenapyr were extremely toxic to the predator mite, causing 100% of mortality two hours after the application. This way, to this population of N. californicus, the releases can be performed safely 3 days after the application, except for cyhexatin (5 days), dicofol and pyridaben (14 days) and chlorfenapyr (21 days), without risk of significant adult mortality rates due to the application of pesticides.

A new genus and species of tarsonemid mite (Acari: Tarsonemidae) from Brazil

Biscutulumnemus neotropicus gen. nov., sp. nov. (Tarsonemidae: Tarsoneminae: Tarsonemini) is described from adult female and male mites, collected on Croton floribundus Spreng., from São José do Rio Preto, State of São Paulo, Brazil. This new genus resembles members of Dendmptus and Tarsonemus, but male mites have two triangular shields anterolaterally to the prodorsal shield and the sejugal apodeme is absent. In addition, Biscutulumnemus differs from Dendroptus by the presence of femoral seta l″ and tibial solenidion φ1 and the presence of a vestigial apodeme I on female mites. Unlike Tarsonemus, Biscutulumnemus has a beaklike gnathosomal capsule, a round flange on leg IV of male mites, and stigmata very close to v1 on the prodorsal shield of female mites. Copyright © 2006 Magnolia Press.

A new species of Hexabdella (Acari: Bdellidae) from Brazil

A new species of the genus Hexabdella Van der Schyff, Theron & Ueckermann, Hexabdella cinquaginta sp.n. is herein described, representing the second species of the family Bdellidae from the neotropical region. It can be distinguished from H. singula by its lobed striae on lateral margins of hysterosoma and by the leg chaetotaxy. A key to species of the genus is presented. Copyright © 2007 Magnolia Press.

Four new species of Xenotarsonemus (Acari: Tarsonemidae) from Brazil

Four new species of Xenotarsonemus Beer (Acari, Tarsonemidae), X. brachytegula, X. pirassunungaensis, X. cerrado and X. spiniphorus, are described based on specimens collected from plants of the Cerrado vegetation in the State of São Paulo, Brazil. Copyright © 2007 Magnolia Press.

A new cunaxid genus with descriptions of two new species from Brazil (Acari: Prostigmata: Bdelloidea: Cunaxidae)

The genus Pseudobonzia Smiley 1975 is revised and divided into two genera. The genus Pseudobonzia Smiley, 1975, with its type species and five other related species, is retained. The remainder of the group is now known as Coleobonzia gen. nov. of which the main characteristics are provided. Coleobonzia argillae (Den Heyer, 1977) is designated as type species for the new genus. Two species from Brazil, viz. Coleobonzia clava sp. nov. and C. moraesi sp. nov. are described and figured. A key to the two genera as well as a key to the Brazilian and South African species of the new genus are provided. Copyright © 2008 Magnolia Press.

A systematic review of feather mites of the pterodectes generic complex (acari: Proctophyllodidae: Pterodectinae) with redescriptions of species described by vladimír cerný

Five species of feather mites originally described in the genus Pterodectes by Vladimir černý (1974) are redescribed: Pterodectes havliki, P. maculatus , P. reticulatus, P. storkani, P. thraupicola and P. troglodytis. The formerly unknown males of P. thraupicola and P. reticulatus and the female of P. maculatus are described for the first time. A synopsis of known species of the Pterodectes generic complex is presented, and species content of the genus Pterodectes is revised. Fifteen species previously included in this genus are transferred to the new genus Amerodectes gen. n.: Amerodectes atyeoi (OConnor et al., 2005) comb. n., A. bilineatus (Berla, 1958) comb. n., A. geothlypis (Berla, 1973) comb. n., A. gracilis (Trouessart, 1885) comb. n., A. maculatus comb. n., A. molothrus (Mironov, 2008) comb. n., A. nordestensis (Berla, 1958) comb. n., A. paroariae (Mironov, 2008) comb. n., A. pitangi (Mironov, 2008) comb. n., A. tangarae (Mironov, 2008) comb. n., A. turdinus (Berla, 1959) comb. n., A. sialiarum (Stoll, 1893) comb. n., A. storkani (černý, 1974) comb. n., A. thraupicola (cčerný, 1974) comb. n., and A. troglodytis (černý, 1974) comb. n. Five species are transferred to the genus Tyrannidectes Mironov, 2008: Tyrannidectes amaurochalinus (Hernandes et Valim, 2006) comb. n., T. banksi (Valim et Hernandes, 2008) comb. n., T. crassus (Trouessart, 1885) comb. n., T. fissuratus (Hernandes et Valim, 2005) comb. n., and T. reticulatus (Cerný, 1974) comb. n.; and one species is moved to the genus Metapterodectes Mironov, 2008: Metapterodectes muticus (Banks, 1909) comb. n. The genus Pterodectes remains monotypic, with the type species P. rutilus Robin, 1877. © Acarina 2010.

Phytoseiidae (Acari: Mesostigmata) on plants of the central region of the Brazilian cerrado

Four surveys of Phytoseiidae species associated with native plants were conducted in ten fragments of Cerrado sensu stricto to determine the species associated with the plants of this region. Twelve of the most common plant species were sampled in each fragment. Twenty six phytoseiid species were recorded during the surveys. Stryphnodendron adstringens was the host plant that had the highest number of species (eight species). Amblyseius neochiapensis Lofego, Moraes and McMurtry 2000 and Neoseiulus tunus (De Leon) 1967 were the most common phytoseiid species. These species occurred on 24 and 20 host species, respectively. Approximately 76 % of the phytoseiids found belonged to the subfamily Amblyseiinae Muma, 1961. Almost 27 % of phytoseiid species recorded were associated with only one plant species. In addition, approximately two thirds of species found in this study also occur in the Atlantic Forest. The comparison of our results from the central areas with previous surveys in peripheral areas of the Cerrado showed that only 12 phytoseiid species were common to both areas.

Two new feather mite species (Acari, pteronyssidae) from the white-barred piculet, picumnus cirratus (Aves, piciformes)

Two new species of the feather mite family Pteronyssidae Oudemans, 1941 are described from the white-barred piculet, Picumnus cirratus Temminck from Brazil: Pterotrogus picumni sp. n. and Ramphastobius scutatus sp. n., representing the first mites described from this host. Pterotrogus picumni sp. n. can be readily distinguished from all previous species of the simplex group by having dorsal crest on femora I and II in both sexes. This is the first representative of the genus Pterotrogus Gaud, 1981 recorded on a host of the genus Picumnus Temminck. Ramphastobius scutatus sp. n. is unique among species of the genus by having in both sexes the prodorsal and scapular shields fused into a single propodonotal shield covering all prodorsum. An updated key to known species of the genus Ramphastobius Gaud, 1981 is presented. © Institute of Parasitology, Biology Centre ASCR.

Fluazuron-induced morphophysiological changes in the cuticle formation and midgut of Rhipicephalus sanguineus Latreille, 1806 (Acari: Ixodidae) nymphs

The present study demonstrated the effects of the arthropod growth regulator, fluazuron (Acatak®), in the formation of the integument and digestive processes of Rhipicephalus sanguineus nymphs fed on rabbits treated with different doses of this chemical acaricide. For this, three different doses of fluazuron (20, 40, or 80 mg/kg) were applied pour on to the hosts (groups II, III, and IV), as well as distilled water to the control group. On the first day after treatment (24 h), the hosts were artificially infested with R. sanguineus nymphs. After full engorgement (7 days), the nymphs were removed, placed on labeled Petri dishes, and kept in biochemical oxygen demand incubator for 7 days. The engorged nymphs were then taken for morphological, histochemical, and histological analyses. The results showed the occurrence of cytological, morphohistological, and histochemical alterations in the integument and midgut of nymphs from all the different treated groups. These alterations occurred at cuticular level in the subdivisions of the cuticle, related to the size of the digestive cells, amount of accumulated blood elements, and digestive residues, as well as the presence of vacuoles in the cytoplasm of the digestive cells. Thus, this study demonstrated that fluazuron acts on the integument and midgut cells of R. sanguineus nymphs fed on treated rabbits and pointed out the possibility of the use of this chemical - which is more specific, less toxic, and less harmful to the environment and nontarget organisms - in the control of R. sanguineus, at least in the nymphal stage of its biological cycle. © 2012 Springer-Verlag.