20 resultados para CTENIDAE


Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper describes an easy, cheap, and safe method of capturing and handling the medically important spider Phoneutria for venom extraction. The method does not injure or kill the spider and allows the extraction of pure venom.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A new species, Isoctenus malabaris, is described from southern Brazil. This spider was abundantly collected with pitfall traps at Araucaria Forests (Mixed Ombrophilous Forest) domain. The activity of this species was studied in three distinct habitats (primary and secondary forests and silvicultures) during 20 months. A bimodal seasonal activity pattern, of males, was observed. Abundance differences of this species between habitats were not significant.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The new ctenid genus Ohvida is proposed to include eight species: Ohvida fulvorufa (Franganillo, 1931) comb. nov. (type species) (=Celaetycheus cabriolatus Franganillo, 1930 syn. nov.; = C. cabriolatus pardosiformis Franganillo, 1930 syn. nov.; = C. fulvorufus afoliatus Franganillo, 1931 syn. nov.), O. isolata (Bryant, 1940) comb. nov., O. vernalis (Bryant, 1940) comb. nov., O. brevitarsus (Bryant, 1940) comb. nov., O. coxanus (Bryant, 1940), comb. nov., and three new species, O. turquino sp. nov. (all species from Cuba), and O. andros sp. nov. and O. bimini sp. nov. (both species from The Bahamas). Species of Ohvida differ from all other ctenid spiders by the presence of a retrodorsal projection on the cymbium of the male pedipalp and by a basal position of the lateral spurs on the female epigyne. The genus Celaetycheus Simon, 1897 is reviewed to only include its type species, C. flavostriatus Simon, 1897 from Brazil. We propose the following synonyms and new combinations: Ctenus ottleyi (Petrunkevitch, 1930) (= Celaetycheus strenuus Bryant, 1942 syn. nov. and C. modestus Bryant, 1942 syn. nov.); Ctenus delesserti (Caporiacco, 1947) comb. nov., and Leptoctenus paradoxus (F.O. P.-Cambridge, 1900) comb. nov. Celaetycheus modestus Bryant, 1942 is considered incertae sedis.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A cladistic analysis was applied to test the monophyly of the genus Isoctenus. The data matrix comprised 28 taxa scored for 53 morphological and two behavioural characters. The analysis resulted in two equally parsimonious trees of 89 steps. The strict consensus was used to discuss the relationships of Isoctenus and related Cteninae genera. Ctenopsis Schmidt is synonymized with Isoctenus. Isoctenus foliifer Bertkau, I. strandi Mello-Leitao, I. eupalaestrus Mello-Leitao, I. janeirus (Walckenaer), I. coxalis (Pickard-Cambridge), I. corymbus Polotow, Brescovit & Pellegatti-Franco and I. malabaris Polotow, Brescovit & Ott are maintained in Isoctenus. Four species currently included in Ctenus are transferred to Isoctenus: I. griseolus (Mello-Leitao) comb. nov., I. taperae (Mello-Leitao) comb. nov., I. herteli (Mello-Leitao) comb. nov. and I. minusculus (Keyserling) comb. nov. The following specific names are synonymized: Ctenus sanguineus Walckenaer, C. semiornatus Mello-Leitao and Ctenopsis stellata Schmidt with Isoctenus janeirus (Walckenaer), Ctenus mourei Mello-Leitao with Isoctenus herteli (Mello-Leitao) and Ctenus pauper Mello-Leitao with Isoctenus strandi Mello-Leitao. Isoctenus sigma Schenkel, described from French Guiana, is transferred to Ctenus. Four species are newly described: Isoctenus areia sp. nov. from Paraiba, Brazil, I. charada sp. nov. and I. segredo sp. nov. from Parana, Brazil, and I. ordinario sp. nov. from south and south-eastern Brazil and north-eastern Argentina. Isoctenus latevittatus Caporiacco is considered species inquirenda. Parabatinga gen. nov. is proposed to include Ctenus brevipes Keyserling. The following synonymies are established: Ctenus taeniatus Keyserling, C. tatarandensis Tullgren, C. anisitsi Strand, C. atrivulvus Strand, C. mentor Strand, C. brevipes brevilabris Strand, Isoctenus masculus Mello-Leitao and Ctenus birabeni Mello-Leitao with Parabatinga brevipes (Keyserling) comb. nov. (C) 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155, 583-614.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Toca new genus is proposed to include two new species: the type species T. bossanova new species from Rio de Janeiro, Brazil, and T samba new species from Parana and Minas Gerais, Brazil. Toca may be related to Caloctenus Keyserling and Gephyroctenus Mello-Leitao, with which it shares the scales on the abdominal dorsum and the epigynum as a single, slightly sclerotized, fold. The genus can be distinguished among the Calocteninae genera by its unique genital structures.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We report herein a case of predation by the ctenid spider Ctenus medius on a leptodactylid frog Leptodactylus marmoratus, observed in a remnant of the Atlantic Forest, municipality of Sao Vicente, São Paulo state, southeast Brazil. This is the first record of predation by C. medius upon L. marmoratus. Nevertheless, due to the high abundance of both groups, we suggest that the interaction between spiders and amphibians could be very common on the floor of the Atlantic Forest.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Five species of Ctenus from the Amazon basin are redescribed: C. delesserti (Caporiacco, 1947), C. falconensis Schenkel, 1953, C. nigritus F.O. Pickard-Cambridge, 1897, C. serratipes F.O. Pickard-Cambridge, 1897 and C. sigma (Schenkel, 1953). Three new synonymies are proposed: Ctenus fulvipes Caporiacco, 1947, C. itatiayaeformis Caporiacco, 1955 and C. scenicus Caporiacco, 1947 with C. serratipes. The female of Ctenus nigritus is described for the first time. The distributional ranges of Ctenus nigritus and C. serratipes are extended. We also present distributional maps of the five redescribed species.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The venom of the ctenid spider Cupiennius salei (Fig.16.1) is rich in components which belong to different functional groups. Besides low molecular mass compounds, the venom contains several disulphide-rich peptides, also called mini-proteins, which act as neurotoxins on ion channels or as enhancers of neurotoxins. Likewise, a variety of small cytolytic peptides, which destroy membranes very efficiently, and enzymes are present in the venom. Neurotoxins with cytolytic activity, cytolytic a-helical small cationic peptides and enzymes most probably attacking connective tissue and phospholipid membranes cause the overall cytotoxic effect of this venom. Synergistic and enhancing interactions between components enable the spider to achieve a maximum of toxicity with a minimum of venom quantity.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A preliminary survey of the spider fauna in natural and artificial forest gap formations at “Porto Urucu”, a petroleum/natural gas production facility in the Urucu river basin, Coari, Amazonas, Brazil is presented. Sampling was conducted both occasionally and using a protocol composed of a suite of techniques: beating trays (32 samples), nocturnal manual samplings (48), sweeping nets (16), Winkler extractors (24), and pitfall traps (120). A total of 4201 spiders, belonging to 43 families and 393 morphospecies, were collected during the dry season, in July, 2003. Excluding the occasional samples, the observed richness was 357 species. In a performance test of seven species richness estimators, the Incidence Based Coverage Estimator (ICE) was the best fit estimator, with 639 estimated species. To evaluate differences in species richness associated with natural and artificial gaps, samples from between the center of the gaps up to 300 meters inside the adjacent forest matrix were compared through the inspection of the confidence intervals of individual-based rarefaction curves for each treatment. The observed species richness was significantly higher in natural gaps combined with adjacent forest than in the artificial gaps combined with adjacent forest. Moreover, a community similarity analysis between the fauna collected under both treatments demonstrated that there were considerable differences in species composition. The significantly higher abundance of Lycosidae in artificial gap forest is explained by the presence of herbaceous vegetation in the gaps themselves. Ctenidae was significantly more abundant in the natural gap forest, probable due to the increase of shelter availability provided by the fallen trees in the gaps themselves. Both families are identified as potential indicators of environmental change related to the establishment or recovery of artificial gaps in the study area.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Seis palmeiras de Attalea phalerata foram amostradas durante a fase aquática (cheia) no Pantanal de Mato Grosso (fevereiro/2001), utilizando-se a metodologia de nebulização de copas "canopy fogging". Este estudo objetivou avaliar a composição, distribuição espacial, guildas comportamentais, biomassa e sazonalidade da comunidade de Araneae em copas dessa palmeira que forma adensamentos monodominantes, típicos nessa região. Um total de 1326 aranhas foram coletadas em 99 m² de área amostral (13,4 + 8,2 indivíduos/m²), representando 20 famílias, sendo Salticidae e Araneidae as mais abundantes. A biomassa total de 704 aranhas em três palmeiras correspondeu a 0.6172 mg de peso seco (0,0123+ 0,04 mg/m²). Dez guildas comportamentais demonstraram a coexistência de diferentes espécies em um mesmo habitat. Representantes de Salticidae, Oonopidae e Ctenidae dominaram entre as caçadoras, e Araneidae e Dictynidae, dentre as tecelãs. A análise de distribuição espacial demonstrou que a maior abundância de aranhas ocorreu na região central da copa, provavelmente devido à quantidade de recursos disponíveis nesse local. A comparação desses resultados com aqueles obtidos durante o período de seca, demonstra diferenças sazonais influenciadas pelo pulso de inundação, principalmente com relação à composição das famílias amostradas entre os períodos de seca e cheia.