Necrophagous diptera associated with wild animal carcasses in southern Brazil

Necrophagous Diptera associated with wild animal carcasses in southern Brazil. The aim of this study was to acquire a better knowledge concerning the diversity of necrophagous Diptera that develop on wild animal carcasses. For this purpose, the decomposition of six wild animal carcasses was observed in order to collect and identify the main species of necrophagous flies associated with the decomposition process. The carcasses were found on highways near the cities of Pelotas and Capão do Leão in the initial stage of decomposition, with no significant injuries or prior larval activity. Four wild animal models were represented in this study: two specimens of Didelphis albiventris Lund, 1840; two Tupinambis merianae Linnaeus, 1758; one Nothura maculosa Temminck, 1815; and one Cerdocyon thous Linnaeus, 1766. A total of 16,242 flies from 14 species were reared in the laboratory, where Muscidae presented the greatest diversity of necrophagous species. Overall, (i) carcasses with larger biomass developed a higher abundance of flies and (ii) the necrophagous community was dominated by Calliphoridae, two patterns that were predicted from published literature; and (iii) the highest diversity was observed on the smaller carcasses exposed to the lowest temperatures, a pattern that may have been caused by the absence of the generalist predator Chrysomya albiceps (Wiedemann, 1819). (iv) An UPGMA analysis revealed a similar pattern of clusters of fly communities, where the same species were structuring the groupings.

Discriminant analysis of skull morphometric characters in Apodemus sylvaticus, A-flavicollis, and A-alpicola (Mammalia; Rodentia) from the Alps

A total of 108 Apodemus skulls from Switzerland, Austria, Italy, France and Germany was studied to determine morphological characteristics useful in identifying individuals as Apodemus sylvaticus (Linnaeus, 1758), A. flavicollis (Melchior, 1834) or A. alpicola Heinrich, 1952. The original assignment of the samples to the three species was based on molar cusp morphology, body proportions, pelage coloration, and allozyme analysis. The 24 measured cranial characters used together accurately discriminated between the three species and correctly classified 100% of the individuals to species. A stepwise discriminant function analysis showed that 6 cranial characters are sufficient to differentiate between the three species, with a correct classification above 97%. Fisher's linear discriminant function coefficients can be used directly for classification of unknown specimens.

Spermiogenesis and spermatozoon ultrastructure of the bothriocephalidean cestode Clestobothrium crassiceps (Rudolphi, 1819), a parasite of the teleost fish Merluccius merluccius (Gadiformes: Merlucciidae)

Spermiogenesis and the ultrastructure of the spermatozoon of the bothriocephalidean cestode Clestobothrium crassiceps (Rudolphi, 1819), a parasite of the teleost fish Merluccius merluccius (Linnaeus, 1758), have been studied by means of transmission electron microscopy. Spermiogenesis involves firstly the formation of a differentiation zone. It is characterized by the presence of two centrioles associated with striated rootlets, an intercentriolar body and an electron-dense material in the apical region of this zone. Later, two flagella develop from the centrioles, growing orthogonally in relation to the median cytoplasmic process. Flagella then undergo a rotation of 90° until they become parallel to the median cytoplasmic process, followed by the proximodistal fusion of the flagella with the median cytoplasmic process. The nucleus elongates and afterwards it migrates along the spermatid body. Spermiogenesis finishes with the appearance of the apical cone surrounded by the single helical crested body at the base of the spermatid. Finally, the narrowing of the ring of arched membranes detaches the fully formed spermatozoon. The mature spermatozoon of C. crassiceps is filiform and contains two axonemes of the 9 + '1' trepaxonematan pattern, a parallel nucleus, parallel cortical microtubules, and electron-dense granules of glycogen. The anterior extremity of the gamete exhibits a short electron-dense apical cone and one crested body, which turns once around the sperm cell. The first axoneme is surrounded by a ring of thick cortical microtubules that persist until the appearance of the second axoneme. Later, these thick cortical microtubules disappear and thus, the mature spermatozoon exhibits two bundles of thin cortical microtubules. The posterior extremity of the male gamete presents only the nucleus. Results are discussed and compared particularly with the available ultrastructural data on the former 'pseudophyllideans'. Two differences can be established between spermatozoa of Bothriocephalidea and Diphyllobothriidea, the type of spermatozoon (II vs I) and the presence/absence of the ring of cortical microtubules.

A taxonomical re-evaluation of the Valais chromosome race of the common shrew Sorex araneus (Insectivora: Soricidae)

The common shrew Sorex araneus Linnaeus, 1758 is subject to intense chromosomal polymorphism. About 65 chromosome races are presently known. One of these chromosome races (the Valais race) is karyologically, morphologically, biochemically, and genetically clearly distinct from all other chromosome races of the species. Recent studies of hybrid zones between the Valais race and other chromosome races in the Swiss and French Alps add further strong evidence for the specific taxonomic status of the Valais race. Chromosomes and diagnostic protein markers reveal sharp frequency clines and strong heterozygote deficits. In one hybrid zone, the maintenance of the strong genetic differentiation of the hybridizing taxa was confirmed by a study with autosomal microsatellites indicating minimal gene flow. A microsatellite marker on the Y-chromosome showed complete absence of male mediated gene flow suggesting hybrid male sterility. To clarify the taxonomic status of this taxon, additional analyses were conducted. A morphometric analysis of the mandible indicated the Valais race is morphologically as distinct from neighbouring chromosome races of S. araneus as from other related Sorex species. In a phylogeny based on complete mitochondrial DNA cytochrome b gene sequences, the Valais race clearly appears as the sister taxon to all other races of S. araneus. Therefore, the chromosome race Valais of S. araneus herein is elevated to specific status and the name Sorex antinorii Bonaparte, 1840 is applied.

Genetic differentiation of common shrew Sorex araneus populations among different alpine valleys revealed by microsatellites

Geographical barriers may affect the genetic structure of populations by reducing gene exchanges among them. In Switzerland, the common shrew Sorer araneus Linnaeus, 1758 is mostly confined to mountainous areas because of a competing sister species, Millet's shrew S. coronatus Millet, 1828, which occupies most of the Swiss lowlands. The structure of common shrew populations found in different alpine valleys may therefore be affected by the topography. Using microsatellites, genetic structuring of seven shrew populations is investigated among four different valleys of, the Swiss Alps. Using the exact G-test, significant genetic structuring is detected between several valleys. Isolation by distance does not fully explain our results. It appears that high mountain ridges (> 2400 m) can significantly reduce gene flow. F- and R-statistics are estimated and compared to the exact G-tests results. Mantel tests show that F-ST, unlike R-ST, is significantly correlated with differentiation. F-ST remains however low even at high differentiation levels, while R-ST has a high variance. We discuss how these results may have wider implications with regards the interpretation of microsatellite data. Finally, a new microsatellite locus, L99, appears to discriminate S. araneus of the Vaud and Cordon races from both S. araneus Valais and S. coronatus.

Spermiogenesis and spermatozoon ultrastructure of the bothriocephalidean cestode Clestobothrium crassiceps (Rudolphi, 1819), a parasite of the teleost fish Merluccius merluccius (Gadiformes: Merlucciidae)

Spermiogenesis and the ultrastructure of the spermatozoon of the bothriocephalidean cestode Clestobothrium crassiceps (Rudolphi, 1819), a parasite of the teleost fish Merluccius merluccius (Linnaeus, 1758), have been studied by means of transmission electron microscopy. Spermiogenesis involves firstly the formation of a differentiation zone. It is characterized by the presence of two centrioles associated with striated rootlets, an intercentriolar body and an electron-dense material in the apical region of this zone. Later, two flagella develop from the centrioles, growing orthogonally in relation to the median cytoplasmic process. Flagella then undergo a rotation of 90° until they become parallel to the median cytoplasmic process, followed by the proximodistal fusion of the flagella with the median cytoplasmic process. The nucleus elongates and afterwards it migrates along the spermatid body. Spermiogenesis finishes with the appearance of the apical cone surrounded by the single helical crested body at the base of the spermatid. Finally, the narrowing of the ring of arched membranes detaches the fully formed spermatozoon. The mature spermatozoon of C. crassiceps is filiform and contains two axonemes of the 9 + '1' trepaxonematan pattern, a parallel nucleus, parallel cortical microtubules, and electron-dense granules of glycogen. The anterior extremity of the gamete exhibits a short electron-dense apical cone and one crested body, which turns once around the sperm cell. The first axoneme is surrounded by a ring of thick cortical microtubules that persist until the appearance of the second axoneme. Later, these thick cortical microtubules disappear and thus, the mature spermatozoon exhibits two bundles of thin cortical microtubules. The posterior extremity of the male gamete presents only the nucleus. Results are discussed and compared particularly with the available ultrastructural data on the former 'pseudophyllideans'. Two differences can be established between spermatozoa of Bothriocephalidea and Diphyllobothriidea, the type of spermatozoon (II vs I) and the presence/absence of the ring of cortical microtubules.

Efeito da alimentação de Schizaphis graminum com genótipos de sorgo no desenvolvimento do predador Cycloneda sanguinea

O pulgão Schizaphis graminum (Rondani) (Hemiptera: Aphididae) é uma das principais pragas do sorgo. O objetivo deste trabalho foi determinar o efeito da alimentação deste inseto com genótipos de sorgo resistentes e suscetíveis no desenvolvimento do predador Cycloneda sanguinea (Linnaeus) (Coleoptera: Coccinellidae). O pulgão foi criado em folhas dos genótipos de sorgo GR 11111 e TX 430 x GR 111, resistentes, GB 3B, de resistência moderada e BR 007B, suscetível ao hemíptero. As larvas de C. sanguinea foram alimentadas diariamente, ad libitum, com ninfas e adultos de S. graminum. A duração das fases de desenvolvimento e a sobrevivência de C. sanguinea não foram influenciadas pelo genótipo. Apenas a duração do quarto ínstar, da fase larval e do período de larva a adulto foram afetadas. O peso de larvas de segundo ínstar de C. sanguinea não foi afetado pelo genótipo. Nos demais ínstares e fase adulta, esse parâmetro foi diferenciado conforme o genótipo de sorgo utilizado como hospedeiro ao pulgão. Os genótipos resistentes GR 11111 e TX 430 x GR 111 não afetam adversamente o desenvolvimento e a fecundidade de C. sanguinea, durante uma geração. Estes genótipos demonstram compatibilidade com o predador e viabilizam o manejo de S. graminum na cultura do sorgo.

Estirpes de Bacillus thuringiensis efetivas contra insetos das ordens Lepidoptera, Coleoptera e Diptera

O objetivo deste trabalho foi selecionar entre 300 estirpes de Bacillus thuringiensis as efetivas simultaneamente contra larvas de Spodoptera frugiperda J.E. Smith e Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae), Anthonomus grandis Boheman (Coleoptera: Curculionidae), Aedes aegypti Linnaeus e Culex quinquefasciatus Say (Diptera: Culicidae). Foram selecionadas duas estirpes de B. thuringiensis, denominadas S234 e S997, que apresentaram atividade contra as três ordens de insetos. As estirpes foram caracterizadas por métodos morfológicos, bioquímicos e moleculares. As mesmas apresentaram duas proteínas principais de 130 e 65 kDa, produtos de reação em cadeia da polimerase de tamanho esperado para a detecção dos genes cry1Aa, cry1Ab, cry1Ac, cry1B e cry2 e cristais bipiramidais, cubóides e esféricos.

Stable isotopes unveil habitat partitioning among the marine mammals off NW Africa and reveal unique trophic niches for two globally threatened species.

Stable isotope abundances of carbon (δ13C) and nitrogen (δ15N) in the bone of 13 species of marine mammals from the northwest coast of Africa were investigated to assess their positions in the local trophic web and their preferred habitats. Also, samples of primary producers and potential prey species from the study area were collected to characterise the local isotopic landscape. This characterisation indicated that δ13C values increased from offshore to nearshore and that δ15N was a good proxy for trophic level. Therefore, the most coastal species were Monachus monachus and Sousa teuszii, whereas the most pelagic were Physeter macrocephalus and Balaenoptera acutorostrata. δ15N values indicated that marine mammals located at the lowest trophic level were B. acutorostrata, Stenella coeruleoalba and Delphinus sp., and those occupying the highest trophic level were M. monachus and P. macrocephalus. The trophic level of Orcinus orca was similar to that of M. monachus, suggesting that O. orca preys on fish. Conservation of coastal and threatened species (M. monachus and S. teuszii) off NW Africa should be a priority because these species, as the main apex predators, cannot be replaced by other marine mammals.

First record of the common bream (Abramis brama) introduced to the Iberian Peninsula

This is the first record of the common bream, Abramis brama (Linnaeus, 1758), introduced into the Iberian Peninsula. Eight individuals of this cyprinid fish species were captured (of a total of 978 fish) in the Boadella Reservoir (Catalonia, Spain) on August 18, 2004. This reservoir is only 14 km away from France, where the bream is native, and contains several exotic freshwater fish that are still not widespread in Spain. The further introduction of species and the illegal translocation of the bream by anglers to other Iberian river basins should be controlled by the Spanish administration

De transmutatione specierum in regno vegetabili

Invocatio: A.J.

De injuriis regni papistici in principes regnumqve Sveciae

Invocatio: I.N.S.S.T.

Composição e caracterização da fauna de mamíferos de médio e grande porte em uma pequena reserva de cerrado em Mato Grosso, Brasil

Este estudo foi realizado na Reserva Biológica Municipal "Mário Viana", Nova Xavantina, MT, objetivando inventariar e avaliar a abundância e diversidade de mamíferos terrestres de médio e grande porte. Para tanto, foram realizadas duas visitas mensais a um transecto com 2.820 m de extensão, durante todo o ano de 2001, para o levantamento de pegadas (rastreamentos) e outras evidências de mamíferos. Um total de 29 espécies foram registradas na área de estudo, sendo que 22 ocorreram no transecto e tiveram suas seqüências individuais de pegadas quantificadas para realização do cálculo dos índices de abundância e de diversidade de Shannon-Wiener (H'). De acordo com seus índices de abundância, as espécies foram classificadas em raras, comuns e abundantes. Dentre outras, onça-parda (Puma concolor - Linnaeus, 1771) e tatu-canastra (Priodontes maximus - Keer, 1792) mostraram-se raras; jaguatirica (Leopardus pardalis - Linnaeus, 1758), e tamanduá-bandeira (Myrmecophaga tridactyla - Linnaeus, 1758), comuns; e cutia (Dasyprocta azarae - Lichtenstein, 1823) e tapeti (Sylvilagus brasiliensis - Linnaeus, 1758), abundantes. O H' encontrado foi 2,40, sendo considerado significativo. O presente trabalho apontou que, apesar de pequena (470 ha), a área de estudo desempenha importante papel para a conservação da mastofauna da região de Nova Xavantina, MT.

Mamíferos de médio e grande porte em um fragmento de mata atlântica, Minas Gerais, Brasil

O grau de ameaça e a importância ecológica dos mamíferos terrestres de médio e grande porte evidenciam a necessidade da busca de informações em inventários e diagnósticos ambientais. Objetivo deste estudo foi inventariar e avaliar a freqüência de ocorrência e riqueza de espécies de mamíferos de médio e grande porte na Estação de Pesquisa, Treinamento e Educação Ambiental (EPTEA) Mata do Paraíso, em Viçosa - MG. A área de estudo foi aleatoriamente percorrida, em busca de evidências indiretas e diretas de mamíferos. Também foram utilizadas armadilhas Tomahawk e fotográficas para o registro e identificação das espécies. Para registrar a freqüência de ocorrência, estabeleceu-se 20 parcelas de 2 x 2 m ao longo de um transecto, as quais foram vistoriadas 29 vezes entre abril de 2005 e abril de 2006. A partir dos dados de freqüência de ocorrência, estimou-se a riqueza de espécies, pelo procedimento Jackknife 1, utilizando o Programa EstimateS. Foram registradas 23 espécies de mamíferos, das quais três estão ameaçadas de extinção: Chrysocyon brachyurus (Illiger, 1815), Leopardus pardalis (Linnaeus, 1758) e Leopardus tigrinus (Schreber, 1775). As espécies silvestres com maior freqüência de registro foram Cerdocyon thous (Linnaeus, 1766), L. tigrinus e L. pardalis. Foi estimada a riqueza de 15 (intervalo de confiança = 0,95) espécies de mamíferos terrestres silvestres para a EPTEA Mata do Paraíso. O presente trabalho mostra que apesar de pequena, a área de estudo desempenha um importante papel na conservação da mastofauna da região de Viçosa - MG.