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| Castillo,Viviana M; Brown,Donald I. |
| Echinolittorina peruviana (Lamarck, 1822), a gonochoric representative of the Littorinidae on the SE Pacific coast, has a male reproductive system adapted for internal fertilization. We describe this system at both macro- and microscopic levéis, particularly the compartmentalized organization of the gonad, and the morphology of the penis. The male reproductive system has a variegated conical gonad-digestive gland complex. The gonad presents three compartments, 1) gametogenic acinar among the glandular acini, 2) periacinar with a layer of fusiform somatic cells and, 3) interacinar with glycogen storage cells shared with glandular acini. Spermatogenesis occurs within the acinar gametogenic compartment, with the germinal line organized in centripetal form... |
| Tipo: Journal article |
Palavras-chave: Mollusca; Microscopic anatomy; Male reproductive system; Littorinidae. |
| Ano: 2008 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022008000200030 |
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| APOLINÁRIO,M.; COUTINHO,R.; BAETA-NEVES,M. H.. |
| The present study examines habitat selection and grazing pressure of the periwinkle Nodilittorina lineolata (Gmelin, 1791) on the rocky shore of Arraial do Cabo, RJ, Brazil (lat. 23°S, long. 43°W). Transfer experiments suggest that periwinkles actively select the mid intertidal, where the cirripede Chthamalus bisinuatus Pilsbry is the dominant sessile invertebrate. We also conducted a caging experiment in the middle intertidal, manipulating grazers and light, to assess the impact of grazing upon microalgal density. Grazing pressure significantly reduced microalgal abundance at the mid-intertidal level, suggesting that food availability plays an important role in the habitat selection of periwinkles on the studied shore. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Brazil; Habitat selection; Intertidal; Littorinidae; Microalgae. |
| Ano: 1999 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0034-71081999000200005 |
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