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Tetranychus evansi Baker & Pritchard is an important pest of Solanaceae in several countries. Introduced accidentally to Africa, it presently occurs in many countries of that continent. In some of them, it is considered a key pest. The suspected area of origin of this mite is South America. The objective of the present study was to identify phytoseiid mites on solanaceous plants in association with T. evansi in south and southeast Brazil for introduction in the African continent for use in a classic biological control program. Almost 1,400 predatory mites of the family Phytoseiidae were collected, on 22 solanaceous species. The Amblyseiinae were the most diverse group in this study. Twenty-three of the species found belong to this subfamily, while only three belong to the Typhlodrominae and two to the Phytoseiinae. The most abundant and most frequent phytoseiid species were Phytoseius guianensis De Leon and Galendromus annectens (De Leon) of the Phytoseiinae and Typhlodrominae, respectively. The most frequent and abundant species of Amblyseiinae was Neoseiulus tunus (De Leon). Phytoseius guianensis and N. tunus were never found in association with T. evansi and G. annectens was found only once in association with it. Two factors suggested Phytoseiulus longipes Evans as the most promising predator found in this study. It could walk very well on tomato leaves infested by T. evansi, without being hampered by the profuse webbing produced by the prey and by the trichomes. In addition, several specimens of both sexes including eggs and nymphs of the predator were found associated with T. evansi on three different plant species and in two different periods of the year, when T. evansi was the only arthropod present on the leaves.

Parasitism of the lizard Tropidurus hispidus by Geckobiella sp. and by larvae of Eutrombicula alfreddugesi was examined in a mountainous area in Chapada do Araripe (07° 16' S and 39° 26' W), southern Ceará State, Brazil. Of the 56 lizards collected (26 females, 27 males, and 3 juveniles), 40 (total prevalence of 71.42%) were infested by mites. Mite-pockets were the sites most heavily infested by E. alfreddugesi larvae, while Geckobiella sp. was found uniformly distributed under scales over the host's entire body. The female specimens of T. hispidus parasitised by E. alfreddugesi had an average infestation rate of 8.57 ± 3.62, 1-27, while the males had an average infestation rate of 11.90 ± 2.63, 1-25. The female specimens parasitised by Geckobiella sp. had an average infestation rate of 5.91 ± 2.28, 1-25, while the males had an average infestation rate of 5.43 ± 1.52, 1-23. Seven specimens were also infested by eggs and immature forms of unidentified mites (average 2.28 ± 0.89, 1-7). There were no significant differences between the total prevalence of mites on adult male (70.4%) and adult female (65.4%) lizards. The body sizes of the hosts did not influence their infestation rates. The average infestation intensity by E. alfreddugesi (10.2 ± 8.7) was significantly greater than the average infestation intensity by Geckobiella sp. (5.9 ± 6.8). T. hispidus is the new host record to Geckobiella mites.

The mite Tetranychus evansi Baker & Pritchard (Tetranychidae) probably originated in South America. Because of its importance as a tomato pest in Africa, an extensive project has been conducted to detect potentially effective natural enemies in South America for the classical biological control of the pest in Africa. A search for the natural enemies of T. evansi was conducted in the Province of Tucumán, northwestern Argentina, in December 2004, and this report describes the results. One hundred predatory mites of the family Phytoseiidae referring to 11 species were collected on 11 examined species of solanaceous plants. The most abundant phytoseiid species collected were Neoseiulus californicus (McGregor) and Euseius concordis (Chant). Adults and immatures of those species, as well as of Neoseiulus idaeus Denmark & Muma, Phytoseiulus fragariae Denmark & Schicha and Proprioseiopsis cannaensis (Muma) were found in association with T. evansi, suggesting that they were developing on the pest. However, because of the possible biological differences between populations of a given species, biological studies evaluating T. evansi as a prey for those predators seem desirable.

SELEÇÃO DE INIMIGOS NATURAIS PARA O CONTROLE BIOLÓGICO DE Tetranychus evansi Baker & Pritchard (ACARI: TETRANYCHIDAE), NA ÁFRICA RESUMO O ácaro vermelho do tomateiro, Tetranychus evansi Baker & Pritchard, é uma praga importante de Solanaceae em diversos países. Introduzido acidentalmente na África, livre de seus inimigos naturais, atualmente encontra-se em muitos países do continente africano, sendo em alguns deles considerado uma praga-chave. Suspeita-se que este ácaro seja originário da América do Sul. Algumas espécies de predadores têm sido reportadas em associação com T. evansi. Testes conduzidos em laboratório por diferentes pesquisadores não têm podido demonstrar a eficiência daquelas como agente de controle daquela praga. O objetivo do presente estudo foi dar continuidade à busca de agentes de controle eficientes, para o controle de T. evansi na África. Para tanto, investigou-se no Brasil e na Argentina a ocorrência desta praga e de seus predadores, principalmente em solanáceas, de outubro de 2002 a dezembro 2004. No total, foram encontrados cerca de 28 000 espécimes de T. evansi no Brasil e 35 000 na Argentina. Naqueles dois países, encontrou-se um total de 15 espécies de predadores da família Phytoseiidae associados a esta praga. Dentre estas, Phytoseiulus longipes Evans foi a que se mostrou mais promissora como agente de controle de T. evansi. Este predador foi encontrado em Uruguaiana-RS, Brasil, sendo esta a primeira constatação desta espécie naquele país. A aceitação de T. evansi como presa para aquela população de P. longipes foi avaliada em laboratório através de dois testes. No primeiro, comparou-se a oviposição média diária do predador quando alimentado com T. evansi e com 3 outras fontes de alimento: Tetranychus urticae Koch, pólen de Ricinus communis L. ou de Typha sp. No segundo, avaliou-se a preferência do predador por T. evansi ou T. urticae. A oviposição média diária de P. longipes foi aproximadamente a mesma (3,4 e 3,5 ovos) quando alimentado com T. evansi ou T. urticae. Não houve oviposição quando o predador foi alimentado com os dois tipos de pólen. Avaliações sucessivas em testes de livre escolha conduzidos no laboratório demonstraram proporções sempre significativamente maiores de P. longipes em folíolos com T. evansi que em folíolos com T. urticae. Posteriormente, a biologia detalhada de P. longipes foi estudada, utilizando-se os alimentos anteriormente citados. A sobrevivência dos diferentes estágios imaturos de P. longipes foi de aproximadamente 94 % e 80 % quando alimentado com T. evansi e T. urticae, respectivamente, e nula quando em presença de ambos os tipos de pólen. A duração da fase imatura do predador alimentado com aquelas presas foi praticamente a mesma (4,7 e 4,8 dias). Phytoseiulus longipes demonstrou alta capacidade de aumento populacional quando alimentado com T. evansi ou com T. urticae. Apresentou uma capacidade inata de aumento em número (r m) de 0,363 e razão finita de aumento em número (λ) de 1,44 quando alimentado com T. evansi; apresentou r m de 0,320 e λ de 1,3...

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Tetranychus bastosi Tuttle, Baker and Sales was described from Ceará state, northeastern Brazil. It has so far been reported from 25 plant species, among which cassava (Manihot esculenta Crants), common bean (Phaseolus vulgaris L.) and papaya (Carica papaya L). Although there is no information about its impact on crop yield, high population levels have been observed on some crops, leading to suppose that damage might occur in some occasions. In this study, fertility life table parameters were calculated for T. bastosi on cassava, common bean and papaya at 25 ± 2 °C, 70 ± 5% RH and photoperiod of 12/12 h. The best performance of T. bastosi occurred on C. papaya and P. vulgaris, on which the intrinsic rate of population increase reached 0.184 and 0.183 female/female/day, respectively. These results agree with the most common occurrence of this mite on papaya and on common bean than on cassava.

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