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1.
Zookeys ; (769): 49-76, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29988790

RESUMO

Morphological, mitochondrial, and nuclear phylogenomic data were combined to address phylogenetic and species delimitation questions in cave-limited Cicurina spiders from central Texas. Special effort was focused on specimens and cave locations in the San Antonio region (Bexar County), home to four eyeless species listed as US Federally Endangered. Sequence capture experiments resulted in the recovery of ~200-400 homologous ultra-conserved element (UCE) nuclear loci across taxa, and nearly complete COI mitochondrial DNA sequences from the same set of individuals. Some of these nuclear and mitochondrial sequences were recovered from "standard" museum specimens without special preservation of DNA material, including museum specimens preserved in the 1990s. Multiple phylogenetic analyses of the UCE data agree in the recovery of two major lineages of eyeless Cicurina in Texas. These lineages also differ in mitochondrial clade membership, female genitalic morphology, degree of troglomorphy (as measured by relative leg length), and are mostly allopatric across much of Texas. Rare sympatry was confirmed in Bexar County, where members of the two major clades sometimes co-exist in the same karst feature. Both nuclear phylogenomic and mitochondrial data indicate the existence of undescribed species from the San Antonio region, although further sampling and collection of adult specimens is needed to explicitly test these hypotheses. Our data support the two following species synonymies (Cicurina venii Gertsch, 1992 = Cicurina madla Gertsch, 1992; Cicurina loftini Cokendolpher, 2004 = Cicurina vespera Gertsch, 1992), formally proposed here. Overall, our taxonomy-focused research has many important conservation implications, and again highlights the fundamental importance of robust taxonomy in conservation research.

2.
Can J Public Health ; 107(6): e514-e519, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28252368

RESUMO

OBJECTIVES: Consumption of energy drinks (ED) raises concerns because of adverse health effects possibly linked with high levels of caffeine and sugar intake. The study looks at the scope of ED consumption as well as some of the associated characteristics. METHODS: Thirty-six public colleges in the Canadian province of Québec agreed to participate in a descriptive cross-sectional study (n = 36). In February 2013, participating colleges invited their students to answer an online questionnaire on consumption of ED, alcoholic ED (AED), and ED in combination with other psychotropic drugs. A descriptive and correlational analysis was carried out. Logistic regressions explored associations between ED consumption and associated characteristics. RESULTS: Of the students who successfully completed the questionnaire and participated in the study (n = 10,283), a low proportion consumed ED (9.1%; n = 935) and/or AED (1.1%; n = 109) at least once a week in the previous month. Although low in proportion, a number of participants reported having used ED with other stimulant psychoactive substances (n = 247) and ≥3 ED/day (n = 193) or ≥3 AED/occasion (n = 167), which can pose a risk for serious adverse effects. Weekly ED consumption was associated with consumption of ≥20 cups of coffee/week, smoking, excessive use of alcohol and past use of cannabis, glues or solvents and amphetamines. CONCLUSION: A majority of respondents are not heavy users of ED, AED, or ED with drugs. Yet, the profiles of ED consumption potentially harmful to health that characterize some participants indicate that the potential health consequences of such behaviour are of concern.


Assuntos
Bebidas Energéticas/estatística & dados numéricos , Estudantes/psicologia , Universidades , Adolescente , Adulto , Bebidas Alcoólicas/estatística & dados numéricos , Estudos Transversais , Feminino , Humanos , Masculino , Psicotrópicos/administração & dosagem , Quebeque , Estudantes/estatística & dados numéricos , Inquéritos e Questionários , Adulto Jovem
3.
Zookeys ; (167): 1-102, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22363201

RESUMO

The spider genus Tayshaneta is revised based on results from a three gene phylogenetic analysis (Ledford et al. 2011) and a comprehensive morphological survey using scanning electron (SEM) and compound light microscopy. The morphology and relationships within Tayshaneta are discussed and five species-groups are supported by phylogenetic analyses: the anopica group, the coeca group, the myopica group, the microps group and the sandersi group. Short branch lengths within Tayshaneta contrast sharply with the remaining North American genera and are viewed as evidence for a relatively recent radiation of species. Variation in troglomorphic morphology is discussed and compared to patterns found in other Texas cave invertebrates. Several species previously known as single cave endemics have wider ranges than expected, suggesting that some caves are not isolated habitats but instead form part of interconnected karst networks. Distribution maps are compared with karst faunal regions (KFR's) in Central Texas and the implications for the conservation and recovery of Tayshaneta species are discussed. Ten new species are described: Tayshaneta archambaultisp. n., Tayshaneta emeraldaesp. n., Tayshaneta fawcettisp. n., Tayshaneta grubbsisp. n., Tayshaneta madlasp. n., Tayshaneta oconnoraesp. n., Tayshaneta sandersisp. n., Tayshaneta sprouseisp. n., Tayshaneta vidriosp. n. and Tayshaneta whiteisp. n. The males for three species, Tayshaneta anopica (Gertsch, 1974), Tayshaneta devia (Gertsch, 1974) and Tayshaneta microps (Gertsch, 1974) are described for the first time. Tayshaneta furtiva (Gertsch, 1974) and Tayshaneta uvaldea (Gertsch, 1974) are declared nomina dubia as the female holotypes are not diagnosable and efforts to locate specimens at the type localities were unsuccessful. All Tayshaneta species are thoroughly illustrated, diagnosed and keyed. Distribution maps are also provided highlighting areas of taxonomic ambiguity in need of additional sampling.

4.
Oecologia ; 112(1): 104-111, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28307365

RESUMO

The edaphic macroarthropod communities of three sites representative of the forest succession in the Lake Duparquet region (situated in the southern part of the boreal forest, Abitibi, Quebec, Canada) were studied. A 47-year-old deciduous forest, a 144-year-old mixed forest, and a 231-year-old coniferous forest form a successional forest gradient with a vegetation composition that is a function of the time elapsed since the last forest fire. Along with forest succession, there is a reduction in macroarthropod community biodiversity. There is a negative gradient for mean total abundance (237-41 individuals), total richness (63-23 species), density (1792-661 individuals/m2), diversity (H' = 1.478-1.007) and equitability (J = 0.821-0.739). These community changes affect saprophagous organisms more than predators. Certain species or taxa show preferences for a particular forest type, such as larval Diptera for the deciduous forest. A comparison of these results with the literature suggests an inverse preference as to habitat choice between microarthropods (Acarina and Collembola) and macroarthropods. From a conservation point of view, macroarthropod biodiversity will be favored by the protection of all forest types since each environment possesses a particular community structure and species.

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