Comportamiento de "Osilinus atratus" (Wood, 1828) ante diferentes sustratos rocosos

[ES] Se estudia el comportamiento del burgado (Osilinus atratus) ante diferentes tipos de sustratos rocosos, tanto en color como en tamaño. Los individuos muestran cierta tendencia a permanecer sobre sustratos de color gris-verdoso, sobre piedras de basalto-fonolitas, muy similares a los colores que abundan en las conchas de esta especie. Igualmente, evitan permanecer sobre sedimentos de pequeña granulometría, incrementándose el tiempo de permanencia cuanto mayor es el grano del sedimento.

A trophic analysis of target species of macrobenthos in a subtropical coast community: a taxa relationship essay

Studies on the feeding habits of aquatic organisms are a requirement for the management and sustainable use of marine ecosystems. The aim of the present research was to analyze the habits and trophic similarities of decapods, starfish and fish in order to propose trophic relationships between taxa, using Hennigian methods of phylogenetic systematics. This new grouping hypothesis, based on shared and exclusive food items and food types, corresponds to the broad taxonomic groups used in the analysis. Our results indicate that algae, Mollusca, Polychaeta, Crustacea, Echinodermata and Actinopterygii are the most exploited common resources among the species studied. Starfish were differentiated from other organisms for being stenophagic, and were grouped for feeding on bivalve mollusks. A larger group of fish and crustaceans shares algae and mainly crustaceans as food items. A third group united all eight species of Actinopterygii. This largest subgroup of fish is typically carnivorous, feeding on Anthozoa and a great quantity of Crustacea. Synodus foetens has a special position among fishes, due to its unique feeding on nematodes. A Euclidean distance dendrogram obtained in a previous publication grouped S. foetens with starfish. That result was based on a few non-exclusive shared similarities in feeding modes, as well as on shared absences of items, which are not an adequate grouping factor. Starfish are stenophagic, eating bivalves almost exclusively. Synodus foetens and Isopisthus parvipinnis have restricted food items, and are thus intermediary in relation to starfish, decapods, and other fish, which are euryphagous. The trophic cladogram displays details of food items, whether or not shared by all species. The resulting trophic analysis is consistent with known historical relationships.

A comunidade de abelhas (Hymenoptera, Apidae s. l.) em uma área restrita de campo natural no Parque Estadual de Vila Velha, Paraná: diversidade, fenologia e fontes florais de alimento

Coletas sistemáticas de abelhas em uma área restrita no Parque Estadual de Vila Velha, Paraná, no período de outubro de 2002 a outubro de 2003, resultaram em 1552 espécimes pertencentes a 181 espécies. Estas espécies estão distribuídas em 58 gêneros, 24 tribos e 5 subfamílias. As plantas visitadas correspondem a 113 espécies, em 72 gêneros e 38 famílias. Megachile com 20 espécies foi o gênero mais rico e Ceratina o gênero mais abundante dentre os gêneros nativos. Apis mellifera foi a espécie mais coletada, correspondendo a 28% do total de indivíduos, e Bombus atratus foi a espécie mais abundante dentre as abelhas nativas. A riqueza e a equitabilidade nos meses foram variáveis, sendo março o mais rico e novembro o de maior equitabilidade. Apesar de tradicionalmente considerados parte das estepes sulinas, os campos de Vila Velha apresentam uma fauna de abelhas contendo várias espécies típicas de cerrado. O igual número de espécies entre as subfamílias Apinae e Halictinae também apontam para uma peculiaridade de sua fauna. Listas de abelhas e plantas coletadas são apresentadas em anexo.

Floral biology of Stachytarpheta maximiliani Scham. (Verbenaceae) and its floral visitors

This study describes the reproductive system of Stachytarpheta maximiliani (Verbenaceae), including its floral biology, nectar and pollen availability and insect foraging patterns, identifying whose species act as pollinators. It was carried out in a Brazilian Atlantic rain forest site. Observations on the pollination biology of the Verbenaceae S. maximiliani indicate that their flowering period extends from September through May. Anthesis occurs from 5:30 a.m. to 5:00 p.m. and nectar and pollen are available during all the anthesis. Many species of beetles, hemipterans, flies, wasps, bees and butterflies visit their flowers, but bees and butterflies are the most frequent visitors. The flowers are generally small, gathered in dense showy inflorescences. A complex of floral characteristcs, such as violet-blue color of flowers, long floral tubes, without scents, nectar not exposed, high concentration of sugar in nectar (about 32%), allowed identification of floral syndromes (melittophily and psicophily) and function for each visitor. The bees, Bombus morio, B. atratus, Trigonopedia ferruginea, Xylocopa brasilianorum and Apis mellifera and the butterflies Corticea mendica mendica, Corticea sp., Vehilius clavicula, Urbanus simplicius, U. teleus and Heraclides thoas brasiliensis, are the most important pollinators.

Malófagos (Phthiraptera, Amblycera, Ischnocera) em aves cativas no sudeste do Brasil

Foram identificadas 12 espécies de malófagos no Parque Zoológico Municipal Quinzinho de Barros, Sorocaba e Fundação Jardim Zoológico, Rio de Janeiro. Ciconiphilus pectiniventris em Cygnus atratus (Anseriformes, Anatidae); Kurodaia sp. em Buteo albicaudatus (Falconiformes, Accipitridae); Degeeriella sp. em Falco sparverius (Falconiformes, Falconidae); Colpocephalum sp. e Goniocotes parviceps em Pavo cristatus (Galliformes, Phasianidae); Goniodes pavonis em Rhea americana (Rheiformes, Rheidae); Colpocephalum cristatae e Heptapsogaster sp. em Cariama cristata (Gruiformes, Cariamidae); Austrophilopterus cancellosus em Ramphastos dicolorus (Piciformes, Ramphastidae); Strigiphilus crucigerus em Otus choliba (Strigiformes, Strigidae); Kurodaia sp. em Rhinoptynx clamator (Strigiformes, Strigidae) e Colpocephalum pectinatum em Speotyto cunicularia (Strigiformes, Strigidae). As relações parasito hospedeiros em Strigiformes são novas no Brasil.

Reproductive biology of Pseudolaelia corcovadensis Porto & Brade (Orchidaceae): melittophyly and self-compatibility in a basal Laeliinae

The floral biology, mating systems and phenology of Pseudolaelia corcovadensis (Orchidaceae), in the "Estação de Pesquisa e Desenvolvimento Ambiental de Peti", São Gonçalo do Rio Abaixo, Minas Gerais state was studied. This species flowers from April to September, with a higher availability of flowers in June and July. The flowers are dark-pink, strongly zygomorphic, and have osmophores and nectar-guides absorbing ultraviolet light. However, the flowers of P. corcovadensis do not present nectar and are pollinated by Bombus (Fervidobombus) atratus Franklin, 1913 (Hymenoptera: Apidae) by deceit. Apparently, the flowers do not form a model-mimic pair with other species in the community, but mimic a generalized melittophilous food-flower. As a consequence, visits are very rare and fruit set is low (18%). Pseudolaelia corcovadensis is self-compatible and presents inbreeding depression in the early stages of development. The phylogenetic position of the genus Pseudolaelia and studies on floral biology in related genera suggest that melittophyly and self-compatibility are basal characters in the subtribe Laeliinae, with subsequent adaptive radiation to pollination by hummingbirds, Lepidoptera, Diptera and other Hymenoptera.

Estudo de caso das levadas agrícolas da Madeira

O ecoturismo é, hoje, uma tendência relevante no Turismo Mundial. Sendo a Região Autónoma da Madeira tão rica em recursos naturais, distinguida pela sua Laurissilva, como Património Mundial Natural da UNESCO, desde 1999, impõe-se a necessidade de explorar sustentadamente parte integrante da Ilha, de que a Levada Nova, situada no concelho da Calheta, é um exemplo significativo. Temos como objetivos principais promover o aproveitamento dos recursos físicos (casas de abrigo do IGA) e naturais já existentes, bem como dinamizar a Levada Nova na vertente turística, no pressuposto de que existem condições para a continuidade deste produto turístico no futuro, tendo em vista a sua sustentabilidade económica. Na metodologia empregue distinguem-se dois âmbitos, o teórico e o prático. Em termos teóricos, recorremos à revisão bibliográfica da temática em estudo. A componente prática baseou-se no trabalho de pesquisa, efetuado no campo, a fim de reconhecer, recolher dados para caraterização do espaço e elaborar o levantamento dos recursos suscetíveis de potenciação ecoturística. Num segundo momento, os dados foram organizados, através do programa de georeferenciação ArcGis, de modo a elaborar um roteiro turístico no espaço definido. Os dados obtidos através da observação direta no terreno - ao longo da Levada Nova - permitem-nos afirmar que a vegetação predominante engloba núcleos florestais de eucaliptos e pinheiros, existindo também pequenos bosquetes de Laurissilva, onde se destacam espécies como o til (Ocotea foetens), o loureiro (Laurus novocanariensis), o perado (Ilex perado), o folhado (Clethra arborea) e o vinhático (Persea indica). Os terrenos abaixo da Levada apresentam variedade nos produtos cultivados (banana, cana-de-açúcar, batata, feijão, vinha e pomares), em consequência de uma irrigação regular e do clima. Como conclusão verificamos a necessidade de uma maior dinamização turística no concelho da Calheta, que contribua para suster a decadência do comércio tradicional e o abandono do património.

Visitantes florais de Lagerstroemia speciosa Pers: (Lythraceae)

Studies were carried out with Lagerstroemia speciosa Pers. on floral reproductive systems, diversity and constancy of visiting insects at different hours of day, the behaviour of these insects at the flowers and the influence of these environmental factors in relation to their visits. The fenology, anthesis and others particularity of this vegetal species was studied. A great diversity of insects was verified visiting the flowers with the predominance of bees. The most frequent and constant species encountered were: Nannotrigona testaceicornis (Lepeletier, 1836) (40,2%), Tetragonisca angustula (Latreille, 1811) (16,9%), Apis mellifera Linnaeus, 1758 (11,8%), Plebeia droryana (Friese, 1900) (9,1 %) e Exomalopsis fulvofasciata (Smith, 1879) (8,5%). The blossoms possessis features of melittophily syndrome and diurnal anthesis. The environmental factors influence the insects foraging activity, mainly temperature, light, time of day, humidity and wind speed. The effective pollinators were the large insects like Bombus morio (Swederus, 1787), Bombus atratus (Franklin, 1913), Centris tarsata (Smith, 1874), Centris flavifrons Fabricius, 1775, Xylocopa suspecta Camargo & Moure, 1988, Xylocopa frontalis (Olivier, 1789) and Eulaema nigrita Lepeletier, 1841.

Contribution of the Malpighian tubules for the maintenance of symbiotic microorganisms in cephalotes ants

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The midgut of Cephalotes ants (Formicidae: Myrmicinae): Ultrastructure of the epithelium and symbiotic bacteria

The ultrastructural analysis of the midgut of Cephalotes atratus. C. clypeatus, and C. pusillus reveled that the midgut epithelium lays on a basal lamina and is composed basically of three cell types: digestive cells, regenerative cells, and goblet cells. In these ants, the rough endoplasmic reticulum, in addition to producing digestive enzymes, is involved in the formation of concretions and ion storage in specialized vacuoles present in the midgut. These concretions are spherocrystals and may contribute to stabilize the pH and to maintain symbiotic bacteria found between microvilli. The ultrastructure analysis of these bacteria revealed the presence of a double envelope typical of gram-negative bacteria. For the three species examined, the ultrastructure similarities are conspicuous, suggesting that this may be the pattern for the genus Cephalotes. Details of the relationship between bacteria and microvilli were examined. (C) 2010 Elsevier Ltd. All rights reserved.

Symbiotic bacteria and the structural specializations in the ileum of Cephalotes ants

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Molecular and ultrastructural profiles of the symbionts in Cephalotes ants

The molecular and ultrastructural profiles of the symbionts found in the midgut and ileum of Cephalotes atratus, Cephalotes clypeatus, and Cephalotes pusillus were determined using the V3 region of the bacterial 16S rDNA gene and transmission electron microscopy (T.E.M.). Two samples of C atratus, three of C clypeatus, and six of C. pusillus were analyzed. The coefficients of similarity ranged from 80% to 94% for the samples of symbionts from C. clypeatus and C. atratus, despite being collected in geographically distant sites. The variability within symbionts found in the samples of C. pusillus varied from 29% to 55%, in samples geographically close as well as distant. PCR-DGGE was effective for the purpose of this study and can be considered a versatile tool to analyze gut microbiota. Details of the ultrastructural aspect of these bacteria are presented. (C) 2010 Elsevier Ltd. All rights reserved.

Ileum of the Cephalotes ants: A specialized structure to harbor symbionts microorganisms

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Proventriculus of Cephalotes ants: A structural and comparative analysis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Sensitivity of ant (Cephalotes) colonies and individuals to antibiotics implies feeding symbiosis with gut microorganisms

Ants in the tribe Cephalotini are exceptional in that they maintain microorganisms in their digestive tract. To understand what these microorganisms mean to the ants, we observed the feeding habits of Cephalotes pusillus and Cephalotes atratus, finding that in nature they feed on extrafloral nectars, homopteran secretions, and bird droppings. Feeding the antibiotic kanamycin to colonies of C. pusillus in the laboratory kills them. Ants desiccate or starve rather than feed on liquids to which the antibiotics gentamycin and netilmycin have been added, but feed and survive on liquids containing nystatin, penicillin, and ampicillin. We identified over 10 microorganisms from the intestine of C. pusillus with different antibiotic-resistance patterns. The bacteria are from the genera Corynebacterium, Brevibacterium, Sphingobacterium, Ochrobactrum, Myroides, Brevundimonas, Alcaligenes, Stenotrophomonas, Moraxella, and Pseudomonas. We hypothesize that the microorganisms provide nutrients to the ants by synthesizing amino acids from carbohydrates and nitrates. We do not know whether the ants collect the bacteria from the environment, but they transmit them to their young. They culture them in their digestive tract, eventually feeding on them.