Recursos de colección

Repositorio da Universidade dos Açores (8.559 recursos)

O Repositório Institucional da Universidade dos Açores desenvolvido no âmbito do projecto RCAAP.

ARQ - CBM - Número 25

Mostrando recursos 1 - 9 de 9

  1. First record of the mealy plum aphid Hyalopterus pruni (Geoffroy), (Homoptera, Aphidoidea) in Madeira Island

    Ilharco, Fernando A.; Soares, António O.

  2. New records of the giant ciliate Zoothamnium niveum (Protozoa, Peritrichia)

    Wirtz, Peter

  3. Effects of fish removal in the Furnas Lake, Azores

    Bio, Ana; Couto, A.; Costa, R.; Prestes, Afonso L.; Vieira, N.; Valente, A.; Azevedo, José M. N.
    The Furnas Lake is a small volcanic, monomitic and increasingly eutrophised water body. Next to agricultural nutrient inputs, high densities of herbivorous fish are thought to contribute to high levels of turbidity in the lake, through zooplankton consumption and re-suspension of the nutrients accumulated in the sediment. According to the alternative state hypothesis a shift from turbid to clear water conditions is favoured by reduction of nutrient concentrations, increased light availability and reduction of planktivorous and benthos-feeding fish stock. To improve water quality in the Furnas Lake, a substantial part of the bottom-feeding fish population (62% of the estimated common carp...

  4. The Gulf of Guinea goby‐shrimp symbiosis and a review of goby‐thalassinidean associations

    Wirtz, Peter
    An undescribed species of the family Gobiidae shares the burrows of the axiid shrimp Axiopsis serratifrons at São Tomé and Príncipe (central eastern Atlantic). In contrast to similar associations of gobiid fishes with alpheid shrimps in the Indo-Pacific and the western Atlantic (where the goby serves as a sentinel for the crustacean and the shrimp leaves the burrow only if the goby remains at the burrow entrance), the axiid appears to completely ignore the goby, which rests near the opening of the burrow. Facultative and obligatory associations of gobies with thalassinidean shrimps are reviewed.

  5. Crustaceans associated with Cnidaria, Bivalvia, Echinoidea and Pisces at São Tomé and Príncipe islands

    Wirtz, Peter; Udekem d'Acoz, Cédric d’
    Symbiotic crustaceans were searched for at sea anemones (Actiniaria), encrusting anemones (Zoantharia), horny coral (Gorgonaria), black coral (Antipatharia), bivalves (Bivalvia), and sea urchins (Echinoidea) at São Tomé and Príncipe Islands (Gulf of Guinea, eastern central Atlantic). Sixteen species of crustaceans were found in association with these invertebrate hosts; eleven of them were new records for the area and two species, belonging to the genera Hippolyte and Heteromysis, were new for science. The thalassinid Axiopsis serratifrons was occasionally associated with an undescribed species of gobiid fish.

  6. Acoetidae (Annelida, Polychaeta) from the Iberian Peninsula, Madeira and Canary islands, with description of a new species

    Palmero, Ana M.; Martínez, Alejandro; Brito, María del Carmen; Núñez, Jorge
    Six species of acoetid polychaetes are reported from the Iberian Peninsula and Macaronesia: Euarche tubifex Ehlers, 1887, Euarche cristata Núñez, n. sp., Eupanthalis kinbergi McIntosh, 1876, Eupolyodontes gulo (Grube, 1855), Polyodontes maxillosus (Ranzani, 1817), and Panthalis oerstedi (Kinberg, 1856). Material was collected during several sublittoral benthic surveys. Descriptions, figures, and a key for the six species are included. The new species Euarche cristata is characterized by its prostomium with cristate or serrated posterior margin.

  7. The speciation of Noctua atlantica (Lepidoptera, Noctuidae) occurred in the Azores as supported by a molecular clock based on mitochondrial COI sequences

    Montiel, Rafael; Vieira, Virgílio; Martins, Tiago; Oliveira, Luísa
    The complete sequence of the cytochrome c oxidase subunit I (COI) gene of Noctua atlantica (Warren, 1905) has been determined and deposited in the NCBI GenBank under the Accession number AY600452. Complete and partial COI sequences of other Lepidoptera have been collected and used to reconstruct a phylogeny with both the Neighbor-Joining and the Maximum Likelihood methods. A molecular clock calibrated for our models indicate a divergence time between Noctua atlantica and Noctua pronuba of 4.7-5.9 Million years, consistent with the geological age of the Azores and suggesting that the speciation process of N. atlantica occurred in this archipelago.

  8. Distribution and abundance of arthropod species in pasture communities of three Azorean islands (Santa Maria, Terceira and Pico)

    Borges, Paulo A. V.
    This work provides evidence that the "hollow curve" is a consistent pattern in the range size distribution of taxonomic and ecological groups of arthropod pasture dwelling species. Many of the inconsistent results relating range size to herbivores diet breadth are probably due to historical constraints in the colonization of the islands and particular characteristics of the habitats studied (e.g. types of resources available). The positive relationship between range size and abundance may be explained by the "resource usage model". However, the slope of the regression line relating distribution to abundance was similar for different groups which suggests there is no difference in...

  9. Diversity and distribution of arthropods in native forests of the Azores archipelago

    Gaspar, Clara; Borges, Paulo A. V.; Gaston, Kevin J.
    Since 1999, our knowledge of arthropods in native forests of the Azores has improved greatly. Under the BALA project (Biodiversity of Arthropods of Laurisilva of the Azores), an extensive standardised sampling protocol was employed in most of the native forest cover of the Archipelago. Additionally, in 2003 and 2004, more intensive sampling was carried out in several fragments, resulting in nearly a doubling of the number of samples collected. A total of 6,770 samples from 100 sites distributed amongst 18 fragments of seven islands have been collected, resulting in almost 140,000 specimens having been caught. Overall, 452 arthropod species belonging to Araneae, Opilionida, Pseudoscorpionida, Myriapoda...

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