Ecologia de Ancylometes gigas (Pickard-Cambridge, 1897) (Araneae: Pisauridae), uma aranha errante que vive próximo a corpos de água em uma floresta tropical úmica

As aranhas caçadoras são importantes modelos de predadores terrestres, porém poucos estudos foram feitos sobre a ecologia destas aranhas em regiões tropicais. Ancylometes gigas (Pickard-Cambridge, 1897) é uma espécie de grande porte de aranha errante que vive próxima a riachos e poças d'água, e muito comum na região amazônica. Realizei marcações, medindo e determinando o sexo dos animais encontrados ao longo de um transecto de 500 m em uma reserva florestal próxima de Manaus, Brasil, com coletas bimestrais durante o ano. Houve uma forte variação temporal no número de indivíduos nas margens do riacho, mas a estrutura de tamanhos manteve-se estável, o que é um forte indício de ausência de sazonalidade reprodutiva e que há uma provável migração sazonal dentro do habitat. A maior concentração de aranhas nas margens dos riachos na época seca deve ser o resultado da redução na disponibilidade de poças nos arredores. A abundância ao longo do riacho também parece mais influenciada pela abundância de poças nos arredores do que pelas características das margens. A população apresentou uma variação temporal no tamanho de adultos, o que é um indício de variação na disponibilidade de alimento, que parece ser menor quando não há poças disponíveis. Houve uma relação significante entre o deslocamento e o tempo entre capturas, mas não houve relação entre deslocamento e tamanho das aranhas, bem como entre sexos. Aparentemente essas aranhas mantém-se fixas em um local por bastante tempo, e ocasionalmente se movem, algumas vezes centenas de metros em poucos dias. Não houve dimosrfismo sexual de tamanho, diferentemente do que tem se constatado para outras aranhas caçadoras simpátricas. Comparada com outras espécies simpátricas, a principal característica ecológica de A. gigas é a sua afinidade por corpos de água, que diferencia sua dieta e estratégia de evitar predadores. Mudanças sazonais na disponibilidade de poças, aparentemente, influenciam suas atividades e o seu crescimento, mas não tanto a ponto de determinar uma sazonalidade reprodutiva marcante

Predation on amphibians by spiders (Arachnida, Araneae) in the Neotropical region

Herein, we report observations about spider predation on anurans (adults and juveniles) in Central Amazonia and a literature review of spiders preying on amphibians in the Neotropical zoogeographic realm. We conducted field observations in Reserva Florestal Adolpho Ducke, Manaus, AM, and observed eight predation events on Bufonidae, Dendrobatidae, Hylidae, and Leptodactylidae frogs. The predators belong to the spider families Ctenidae, Pisauridae and Theraphosidae. Besides the families of spiders found in this study, two others - Lycosidae and Sparissidae - were found in literature. Frogs from families Centrolenidae and Microhylidae, and a caecilian (Gymnophiona, Caeciliidae) were found in literature also. There is a significant correlation between the length of the anuran (snout-vent length) and the length of spiders (cephalotorax and abdomen length). The size of the spider is similar or slightly lesser than the anuran prey. In general, the spiders preyed on adult and juvenile frogs in the breeding season. Spiders are opportunistic predators and prey on small frogs. Theraphosidae prey upon sub adults of large anurans and caecilians. As spiders can reach high densities on the forest floor - especially species of the genera Ctenus and Ancylometes - this interaction may be ecologically important for breeding anurans. Our reports and literature data provide evidence that spiders commonly prey on amphibians in Neotropic, but the impact of predation on populations of amphibians is unknown. © 2005 Departamento de Ciências Biológicas - ESALQ - USP

Predation on amphibians by spiders (Arachnida, Araneae) in the Neotropical region

Herein, we report observations about spider predation on anurans (adults and juveniles) in Central Amazonia and a literature review of spiders preying on amphibians in the Neotropical zoogeographic realm. We conducted field observations in Reserva Florestal Adolpho Ducke, Manaus, AM, and observed eight predation events on Bufonidae, Dendrobatidae, Hylidae, and Leptodactylidae frogs. The predators belong to the spider families Ctenidae, Pisauridae and Theraphosidae. Besides the families of spiders found in this study, two others - Lycosidae and Sparissidae - were found in literature. Frogs from families Centrolenidae and Microhylidae, and a caecilian (Gymnophiona, Caeciliidae) were found in literature also. There is a significant correlation between the length of the anuran (snout-vent length) and the length of spiders (cephalotorax and abdomen length). The size of the spider is similar or slightly lesser than the anuran prey. In general, the spiders preyed on adult and juvenile frogs in the breeding season. Spiders are opportunistic predators and prey on small frogs. Theraphosidae prey upon sub adults of large anurans and caecilians. As spiders can reach high densities on the forest floor - especially species of the genera Ctenus and Ancylometes - this interaction may be ecologically important for breeding anurans. Our reports and literature data provide evidence that spiders commonly prey on amphibians in Neotropic, but the impact of predation on populations of amphibians is unknown. © 2005 Departamento de Ciências Biológicas - ESALQ - USP

A new Amazonian Cryptocellus westwood (arachnida, ricinulei)

Cryptocellus icamiabas sp. nov. is described from an adult male from Amazonas state, Brazil. The new species is a member of the Amazonian foedus group, and is closest to Cryptocellus abaporu Bonaldo & Pinto-da-Rocha, 2003, Cryptocellus becki Platnick, 1977, and Cryptocellus simonis Hansen & Sorensen, 1904. The distribution pattern and morphology of the foedus group are briefly discussed. Copyright © 2007 Magnolia Press

Avanços na caracterização morfológica das sensilas tarsais de Heliconius erato phyllis (lepidoptera: nymphalidae)

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A forma e a distribuição espacial dos alçapões de Actinopus tarsalis (araneae: actinopodidae)

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Avanços na caracterização morfológica das sensilas tarsais de Heliconius erato phyllis (lepidoptera: nymphalidae)

12

A forma e a distribuição espacial dos alçapões de Actinopus tarsalis (araneae: actinopodidae)

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Palpigradi

ORDER PALPIGRADI EUKOENENIIDAE janetscheki Condé, 1993: 282, figs. 2–4. Eukoenenia Paratypes: female and immature, INPA-PP 2 (K 18 TM); male and 2 immatures, INPA-PP 3 (R 19 TM); Brazil, Amazonas, Manaus, Rio Tarumã-Mirim (03°02'S, 60 ° 17 ' W), J.M.G. Rodrigues leg., 25.VIII. 1982; immature female, INPA-PP 4; Reserva Florestal Adolpho Ducke (02° 55 'S, 59 ° 59 'W), J. Wellington de Morais leg., 8.IX. 1982 (K 15 RD). Remarks: The holotype male of this species was deposited in INPA but is currently missing. Details for the specimen are: INPA-PP 1, slide; Brazil, Amazonas, Manaus, Rio Tarumã-Mirim (03° 02'S, 60 ° 17 'W), J.M.G. Rodrigues leg., 25.VIII. 1982 (K 21 TM).Published as part of Saturnino, Regiane, Tourinho, Ana Lúcia & Azevedo, Clarissa Salette De, 2009, Catalogue of type specimens of invertebrates in the collection of the Instituto Nacional de Pesquisas da Amazônia, Manaus, Brazil. IV. Arachnida: Acari, Palpigradi, Pseudoscorpiones, Ricinulei and Schizomida, pp. 28-40 in Zootaxa 1973 on page 38, DOI: 10.5281/zenodo.18508

Predation on amphibians by spiders (Arachnida, Araneae) in the Neotropical region

Herein, we report observations about spider predation on anurans (adults and juveniles) in Central Amazonia and a literature review of spiders preying on amphibians in the Neotropical zoogeographic realm. We conducted field observations in Reserva Florestal Adolpho Ducke, Manaus, AM, and observed eight predation events on Bufonidae, Dendrobatidae, Hylidae, and Leptodactylidae frogs. The predators belong to the spider families Ctenidae, Pisauridae and Theraphosidae. Besides the families of spiders found in this study, two others – Lycosidae and Sparissidae - were found in literature. Frogs from families Centrolenidae and Microhylidae, and a caecilian(Gymnophiona, Caeciliidae) were found in literature also. There is a significant correlation between the length of the anuran (snout-vent length) and the length of spiders (cephalotorax and abdomen length). The size of the spider is similar or slightly lesser than the anuran prey. In general, the spiders preyed on adult and juvenile frogsin the breeding season. Spiders are opportunistic predators and prey on small frogs. Theraphosidae prey upon sub adults of large anurans and caecilians. As spiders can reach high densities on the forest floor - especially species of the genera Ctenus and Ancylometes - this interaction may be ecologically important for breeding anurans.Our reports and literature data provide evidence that spiders commonly prey on amphibians in Neotropic, but the impact of predation on populations of amphibians is unknown