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1.
Zootaxa, v. 5411, n. 1, p. 001-071
Article de Anglais | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-5292

RÉSUMÉ

This paper presents a taxonomic revision of the genus Tullgrenella Mello-Leitão, 1941. Four new species are described: Tullgrenella aisenbergae Marta, sp. nov. (Brazil) (♂♀), T. legalissima Marta & Hagopián sp. nov. (Uruguay) (♀), T. galianoae Marta, sp. nov. (Brazil) (♂♀) and T. sciosciae Marta & Bustamante sp. nov. (Brazil) (♂♀). The males of T. corrugata Galiano, 1981 and T. peniaflorensis Galiano, 1970, and the female of T. selenita Galiano, 1970 are described for the first time. An updated diagnosis for the genus is provided based on the detailed comparative morphological studies. In addition, we present a proposal and discussion about the species groups of Tullgrenella based on the putative synapomorphies as well as the updated distribution of the genus in South America.

2.
Front Genet ; 9: 138, 2018.
Article de Anglais | MEDLINE | ID: mdl-29755504

RÉSUMÉ

Elasmobranchs, the group of cartilaginous fishes that include sharks and rays, are especially vulnerable to overfishing due to low fecundity and late sexual maturation. A significant number of elasmobranch species are currently overexploited or threatened by fisheries activities. Additionally, several recent reports have indicated that there has been a reduction in regional elasmobranch population sizes. Brazil is an important player in elasmobranch fisheries and one of the largest importers of shark meat. However, carcasses entering the shark meat market have usually had their fins and head removed, which poses a challenge to reliable species identification based on the morphology of captured individuals. This is further complicated by the fact that the internal Brazilian market trades several different elasmobranch species under a common popular name: "cação." The use of such imprecise nomenclature, even among governmental agencies, is problematic for both controlling the negative effects of shark consumption and informing the consumer about the origins of the product. In this study, we used DNA barcoding (mtDNA, COI gene) to identify, at the species level, "cação" samples available in local markets from Southern Brazil. We collected 63 samples traded as "cação," which we found to correspond to 20 different species. These included two teleost species: Xiphias gladius (n = 1) and Genidens barbus (n = 6), and 18 species from seven elasmobranch orders (Carcharhiniformes, n = 42; Squaliformes, n = 3; Squatiniformes, n = 2; Rhinopristiformes, n = 4; Myliobatiformes, n = 3; Rajiformes, n = 1; and Torpediniformes, n = 1). The most common species in our sample were Prionace glauca (n = 15) and Sphyrna lewini (n = 14), while all other species were represented by four samples or less. Considering IUCN criteria, 47% of the elasmobranch species found are threatened at the global level, while 53% are threatened and 47% are critically endangered in Brazil. These results underline that labeling the meat of any shark species as "cação" is problematic for monitoring catch allocations from the fishing industry and discourages consumer engagement in conservationist practices through informed decision-making.

3.
Genet. mol. biol ; Genet. mol. biol;31(4): 843-849, Sept.-Dec. 2008. graf, tab
Article de Anglais | LILACS | ID: lil-501443

RÉSUMÉ

The Floripa H and L rat lines, selected for high and low locomotion in the central aversive area of an open field, a widely used emotionality test, were proposed as a model for studying the genetic basis of anxiety. The present study aimed to verify if the QTL Ofil1, mapped to rat chromosome 4 and previously identified as being related to emotionality in another population of rats, contributes to the behavioral variability observed in the Floripa rat lines. To this purpose, rats of five generations of selective breeding were genotyped for two polymorphic markers, D4RAT59 and D4MGH27, flanking Ofil1. Changes in genotype and allele frequencies throughout generations were evaluated in both H and L lines, in order to assess if the bidirectional selection based on behavioral scores induced divergent changes in the genotype of this genome region. There were significant changes in genotype frequencies for both molecular markers, however, only the genotype variations of the D4RAT59 marker were significantly correlated with the variations in the selected phenotype. This result suggests that the region of the genome near D4RAT59 contains one or more genes contributing to the interindividual variation in central locomotion in the open field test.


Sujet(s)
Animaux , Rats , Troubles anxieux , Modèles animaux , Locus de caractère quantitatif , Consommation d'alcool , Génotype , Polymorphisme génétique
4.
Neotrop. entomol ; 34(3): 363-374, May-June 2005. ilus, tab, graf
Article de Anglais | LILACS | ID: lil-421441

RÉSUMÉ

Estudos em populações de espécies invasoras permitem entender como os invasores reagem às novas condições bióticas e abióticas, e como espécies nativas reagem à invasão. Avaliou-se a eficiência de colonização da invasora Zaprionus indianus (Gupta), na área urbana da cidade de Porto Alegre, RS. Amostras de moscas foram tomadas de três parques urbanos, e índices ecológicos foram usados baseados na freqüência das espécies amostradas. Os índices foram calculados para sítios de oviposição e alimentação separadamente. A maior freqüência de Z. indianus comparada aos outros drosofilídeos foi registrada nas estações de temperaturas médias maiores, tanto para o componente sítio de alimentação como o de oviposição. Nessas mesmas estações, e para ambos os componentes, foram encontrados os maiores valores do índice de dominância (D) e os menores valores de diversidade (H'). Uma análise dos valores do índice de similaridade de Morisita mostrou que o Jardim Botânico e o Parque Farroupilha apresentam maior similaridade em termos de diversidade para o componente sítio de oviposição. Para o componente sítio de alimentação a maior similaridade foi entre Parque Farroupilha e Parque Gabriel Knijnik. Apesar de os três parques apresentarem algumas particularidades, a facilidade de estabelecimento de Z. indianus nesses locais parece ter sido a mesma. A chegada da invasora parece estar promovendo ajustes nas estratégias de sobrevivência das espécies residentes, pelo menos em certos períodos quando a freqüência das populações da invasora aumenta significantemente. Entretanto, pelo menos a maioria das espécies parece ter condições de coexistir com a invasora.


Sujet(s)
Diptera/croissance et développement
SÉLECTION CITATIONS
DÉTAIL DE RECHERCHE