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| Absalão,Ricardo Silva; Roberg,Renata Alves Pinheiro. |
| The Littorina ziczac (Gmelin, 1791) species complex was studied in Rio de Janeiro State, southeastern Brazil. The occurrence of three species was confirmed, through the analysis of penis morphology: L. ziczac (Gmelin, 1791), L. lineata d'Orbigny, 1841 and L. lineolata d'Orbigny, 1840. There is a correlation between the morphology of the penis and shell shape, thus it was possible to make a discrimination model based in conchologic data, with an efficiency of 75%. However, this model cannot be applied to others samples that weren't included in its formulation, due to phenotypic plasticity of the shell caused by biotic and abiotic factors. In the 9 areas studied L. lineolata was always the most abundam species. No vertical stratification in the distribution... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Littorina; Species complex; Vertical distribution; Biochemistiy; Rio de Janeiro; Brazil. |
| Ano: 1999 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751999000200005 |
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| Sergievsky, So; Granovitch, Ai; Sokolova, Im. |
| The results of a 14-year survey of the populations of L. saxatilis and L. obtusata from one locality in the Kandalaksha Bay of the White Sea are presented. The periwinkles were found to be hosts of 10 castrating trematode species. Microphallus piriformes was the most abundant species with infection prevalence often exceeding 50%. Year-to-year variation of the infection prevalence was correlated in the two host species, probably reflecting fluctuations in the influx of trematode eggs to the shore. Long-term changes in population density are associated with the variation of the age structure of the winkles, suggesting a dependence of the population density on the success of the recruitment. Fluctuations in abundance and age composition were correlated in L.... |
| Tipo: Text |
Palavras-chave: Long-term; Population dynamics; Demography; Littorina; Trematoda. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00093/20395/18062.pdf |
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