Ovoposició en poblacions de "Physa acuta" "(Gastropoda: Pulmonata)" mantingudes al laboratori

Autors/ores

  • Joan-Antoni Vela i Fernàndez

Resum

The ovipositional parameter, number of egg masses/snailxday, has been recorded in laboratory-kept populations of Physa acuta in the period 1973-1975. The results show a clear non circadian rhythm with a period slightly over 3 days long, and whose extent depends on the provenance of the populations being not related to the seasonal period. Further, the rhythm found is significatively correlated to the atmospheric ressure change. So, the suggestion is made that some geophysical actor correlated to the atmospheric pressure affects the ovipositional activity in Physa acuta. Moreover, it is shown too that the change of water stimulates it.

Descàrregues

Publicat

2005-05-12