999 resultados para the otherworld


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The clingfish Gobiesox barbatulus shows nocturnal feeding activity, spending most part of the day stationary and adhered to the inferior part of stones. To feed, this species uses the sit-and-wait and particulate feeding tactics. It shows a carnivorous feeding habit mostly consuming small benthic crustaceans. It can move in two ways: (1) "stone-by-stone", sliding its ventral sucker disc across each stone and (2) "surf", when it takes advantage of the energy of the ebbing tide to quickly cross a distance up to four times its body length. Its reproductive season occurs between the end of spring and the beginning of summer, during which time it lays about 2,000 adhesive eggs of 1 mm each in a single layer under stones. It has more than one egg-laying session per reproductive season, therefore showing several different developmental stages. It performs fanning, mouthing and guarding of the eggs as forms of parental care. Data shown here also indicates that G. barbatulus has some shelter fidelity, being probably territorial.

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The new species herein described, collected in the Jacuí and Uruguay River basins, Rio Grande do Sul, Brazil, can be distinguished from the already known species of the genus, but Oligosarcus jenynsii, O. perdido, O. acutirostris, O. solitarius and O. hepsetus, by the number of perforated lateral line scales. It shares with the first two species the absence of a premaxillary foramen, present in the last three species and differs from O. jenynsii by having a smaller orbital diameter and the tip of the pectoral fin failing to reach the pelvic-fin origin, and from O. perdido by the presence of more horizontal scale rows around the caudal peduncle.

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The troglobitic armored catfish, Ancistrus cryptophthalmus (Loricariidae, Ancistrinae) is known from four caves in the São Domingos karst area, upper rio Tocantins basin, Central Brazil. These populations differ in general body shape and degree of reduction of eyes and of pigmentation. The small Passa Três population (around 1,000 individuals) presents the most reduced eyes, which are not externally visible in adults. A small group of Passa Três catfish, one male and three females, reproduced spontaneously thrice in laboratory, at the end of summertime in 2000, 2003 and 2004. Herein we describe the reproductive behavior during the 2003 event, as well as the early development of the 2003 and 2004 offsprings, with focus on body growth and ontogenetic regression of eyes. The parental care by the male, which includes defense of the rock shelter where the egg clutch is laid, cleaning and oxygenation of eggs, is typical of many loricariids. On the other hand, the slow development, including delayed eye degeneration, low body growth rates and high estimated longevity (15 years or more) are characteristic of precocial, or K-selected, life cycles. In the absence of comparable data for close epigean relatives (Ancistrus spp.), it is not possible to establish whether these features are an autapomorphic specialization of the troglobitic A. cryptophthalmus or a plesiomorphic trait already present in the epigean ancestor, possibly favoring the adoption of the life in the food-poor cave environment. We briefly discuss the current hypotheses on eye regression in troglobitic vertebrates.

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The systematics of the Glandulocaudinae is reviewed in detail and justification for the recognition of the group as a subfamily is discussed. The subfamily Glandulocaudinae consists of three genera: Lophiobrycon with one species plesiomorphic in some anatomical features but some others exclusively derived relative to the species in the other genera; Glandulocauda with two species intermediate in phylogenetic derivation; and Mimagoniates with seven species (one new), all more phylogenetically derived concerning their pheromone producing caudal-fin organs and with other anatomical characters presumably more derived than in the species of the other genera. Glandulocauda melanogenys Eigenmann, 1911, is considered a junior synonym of Hyphessobrycon melanopleurus Ellis, 1911. A replacement name, Glandulocauda caerulea Menezes & Weitzman, is proposed for G. melanopleura Eigenmann, 1911. Gland cells found in the caudal-fin organs of all species are histologically indistinguishable from club cells and probably secrete a pheromone during courtship. The club cells are associated with somewhat modified to highly derived caudal scales forming a pheromone pumping organ in the more derived genera and species. This subfamily is distributed in freshwaters of eastern and southern Brazil, Paraguay, and northeastern Uruguay.

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A second inseminating species bearing club cells organized into an anal-fin gland in sexually active males belonging to the genus Bryconadenos was recently discovered in the rio Xingu drainage and is described as new. It is distinguished from B. tanaothoros by the presence of a conspicuous dark blotch at the humeral region, and fewer scale rows between dorsal-fin origin and anal-fin origin. Males of B. weitzmani have longer pelvic fins at sizes beyond 30 mm SL. Bryconadenos weitzmani is further distinguished from B. tanaothoros by the cup shape of the anal-fin gland, its lower part much more developed than the upper, whereas in B. tanaothoros there is just a slit separating the almost equally developed upper and lower parts.

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A cave population of the armored catfish Isbrueckerichthys alipionis is reported from the Santana Cave, in the rio Betari watershed, Upper Ribeira karst area, Iporanga, São Paulo State, southeastern Brazil. The cave population was compared to an epigean population of I. alipionis and no significant differences where found in morphology or degree of pigmentation. As the cave population is known for at least 30 years and is apparently isolated from epigean streams, it is classified as troglophilic. The discovery of this troglophilic species in the Santana Cave is an additional strong argument for the conservation of that cave.

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The genus Callistomys belongs to the rodent family Echimyidae, subfamily Echimyinae, and its only living representative is Callistomys pictus, a rare and vulnerable endemic species of the state of Bahia, Brazil. Callistomys has been previously classified as Nelomys, Loncheres, Isothrix and Echimys. In this paper we present the karyotype of Callistomys pictus, including CBG and GTG-banding patterns and silver staining of the nucleolus organizer regions (Ag-NORs). Comments on Callistomys pictus morphological traits and a compilation of Echimyinae chromosomal data are also included. Our analyses revealed that Callistomys can be recognized both by its distintinctive morphology and by its karyotype.

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Este artigo analisa, pela primeira vez na literatura, o impacto dos sindicatos de trabalhadores em vários indicadores de desempenho econômico de firmas industriais brasileiras. Realizou-se uma pesquisa retrospectiva sobre a densidade sindical de 1000 estabelecimentos industriais brasileiros e seus resultados foram combinados aos indicadores de desempenho econômico da Pesquisa Industrial Anual (PIA) de 1990 a 2000. Os resultados indicam que a relação entre a densidade sindical na firma e seus salários, emprego e produtividade, é não-linear, ou seja, um aumento no grau de sindicalização leva a um melhor desempenho, porém a taxas decrescentes. Observou-se, também, uma relação negativa entre sindicalização e rentabilidade. Finalmente, estabelecimentos que introduziram mecanismos de 'participação nos lucros' aumentaram sua produtividade e rentabilidade no período e pagaram maiores salários nas firmas onde o grau de sindicalização era maior.

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The harvestmen subfamily Hernandariinae is reviewed and a new classification is proposed based on cladistic analysis using 67 morphological characters. The subfamily is composed of six genera and 23 species and occurs in south-southeastern Brazil, Paraguay, and northeastern Argentina. Fourteen new combinations are proposed: Hernandaria armatifrons (Roewer, 1917); H. una (Mello-Leitão, 1927); Acrogonyleptes granulatus (H. Soares, 1966); A. pectinifemur (Soares & Soares, 1947); Acanthogonyleptes alticola (Mello-Leitão, 1922); A. editus (Roewer, 1943); A. fallax (Mello-Leitão, 1932); A. fulvigranulatus (Mello-Leitão, 1922); A. marmoratus (Mello-Leitão, 1940); A. pictus (Piza, 1942); A. singularis (Mello-Leitão, 1935); A. soaresi (Mello-Leitão, 1944); A. variolosus (Mello-Leitão, 1944). Seven synonymies are proposed: Proweyhia Mello-Leitão, 1927 and Metaxundarava Mello-Leitão, 1927 = Hernandaria Sørensen, 1884; Apembolephaenus calcaratus Soares & Soares, 1945 = H. armatifrons (Roewer, 1917); Sphaerobunus Rower, 1917 and Paraproweyhia Soares & Soares, 1947 = Acrogonyleptes Roewer, 1917; Paraproweyhia curitibae Soares & Soares, 1947 = Acrogonyleptes exochus (Mello-Leitão, 1931); and Melloleitaniana curitibae B. Soares, 1943 = Acrogonyleptes spinifrons Roewer, 1917. Three species are revalidated: Acrogonyleptes granulatus (H. Soares, 1966), A. pectinifemur (Soares & Soares, 1947), and A. spinifrons Roewer, 1917. Seven new species are described: Hernandaria sundermannorum sp. nov. (São Paulo State, Brazil), Hernandaria anitagaribaldiae sp. nov. (Santa Catarina State, Brazil), Hernandaria zumbii sp. nov. (Santa Catarina State, Brazil), Hernandaria chicomendesi sp. nov. (Santa Catarina State, Brazil), Acrogonyleptes cheguevarai sp. nov. (Rio Grande do Sul State, Brazil), Pseudotrogulus pagu sp. nov. (São Paulo State, Brazil), Pseudotrogulus trotskyi sp. nov. (Paraná State, Brazil).

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During the exploration and mapping of new caves in Serra do Ramalho karst area, southern Bahia state, cavers from the Grupo Bambuí de Pesquisas Espeleológicas - GBPE (Belo Horizonte) noticed the presence of troglomorphic catfishes (species with reduced eyes and/or melanic pigmentation), which we intensively investigated with regards to their ecology and behavior since 2005. Non-troglomorphic fishes regularly found in the studied caves were included in this investigation. We present here data on the natural history of two troglobitic (exclusively subterranean troglomorphic species) fishes - Rhamdia enfurnada Bichuette & Trajano, 2005 (Heptapteridae; Gruna do Enfurnado) and Trichomycterus undescribed species (Trichomycteridae; Lapa dos Peixes and Gruna da Água Clara), and non-troglomorphic Hoplias cf. malabaricus, probably a troglophile (able to form populations both in epigean and subterranean habitats) in the Gruna do Enfurnado, and Pimelodella sp., a species with a sink population in the Lapa dos Peixes.

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After an ichthyofaunistic survey in several epigean (surface) water bodies of the Serra do Ramalho, southern Bahia, conducted in May 2007, 44 species were recorded; in addition, three non-troglomorphic (normally eyed and pigmented) and two troglomorphic species were recorded only in caves, totaling 49 species of fishes for the area, which represents a little more than one fourth of the total registered in the literature for the entire Rio São Francisco basin. In these caves, which have been studied since 2005, eight non-troglomorphic species were sampled and their presence in both epigean and subterranean habitats, associated to the lack of morphological differences, indicate that they may be either troglophiles (species encompassing individuals able to live and complete their life cycle either in the surface or in the subterranean environment), trogloxenes (individuals regularly found in subterranean habitats, but which must return periodically to the surface in order to complete their life cycle) or even accidental in caves. In addition, two troglomorphic species (with reduced eyes and melanic pigmentation when compared to close epigean relatives), belonging respectively to the genera Rhamdia and Trichomycterus, were recorded exclusively in caves, thus classified as troglobites. Interestingly, no epigean representative of the genus Trichomycterus was collected. The new data are integrated into updated lists of Brazilian troglobitic and troglophilic fishes, based on published data and new records recently confirmed.

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Sickesia tremembe sp. nov. is described from Piauí, Northeast Brazil (type-locality: Sete Cidades National Park, Brasileira and Piracuruca municipalities). It differs from S. usta and S. helmuti by the clavate male femur IV and chelicerae segment I with a pair of large tubercles on retrolateral surface. The Stygnidae Stygnus polyacanthus (Mello-Leitão, 1923); the Cosmetidae, Gryne pluriarcuata Mello-Leitão, 1936 and undetermined species of Paecilaema and Gryne and also representatives of Escadabiidae and Sclerosomatidae (Gagrellinae) are recorded from this state, for the first time.

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Protimesius osvaldoi sp. nov. is described from the Reserva Biológica de Sooretama, state of Espírito Santo, southeastern Brazil, being the first record of Stygnidae from this State and the southernmost record of the family in the Brazilian Atlantic Forest (hitherto, the family was recorded down to Bahia only), extending in 210 km south of the previously known distribution. This is a large species, with armature of leg IV very reduced and penial morphology differing from the closest counterparts mainly in the ventral plate, which recedes deeply at the lateral borders and has the distal margin curved ventrally and by the presence of two small intermediate setae. Protimesius Roewer, 1913 consisted hitherto of 17 species, recorded from northern/northeastern Brazil and Amazonia of adjacent countries. A key is given for the 17 species of Protimesius for which males are known.

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On the first tachinid fly (Diptera, Tachinidae) carrying Asclepiadoideae pollinaria in the Neotropical Region. This paper reports the first Neotropical Tachinidae species possibly associated to pollination of Asclepiadoideae: a female of Euacaulona sumichrasti Townsend, 1908 (Diptera, Tachinidae, Phasiinae, Trichopodini) carrying pollinaria of Gonolobus parviflorus Decne., 1844 (Apocynaceae, Asclepiadoideae, Asclepiadeae: Gonolobinae) attached to its proboscis. The fly specimen was collected in Paraguay, Departamento Canindeyú. The pollinarium is illustrated and described herein. This represents the first anthophilous record to G. parviflorus and to the genus.