Locomotory responses of the cave cyprinid Phreatichthys andruzzii to chemical signals from conspecifics and related species: new findings

Previous research on chemical communication among hypogean fishes have sugg ested that these species are attracted, as are epigean species, by the odou r of non-injured conspecifics. Considerations on the biological meaning of such responses and some doubts about the reliability of the experimental pr ocedure previously utilised, have led us to reconsider the matter and verif y the results already obtained in the cave cyprinid Phreatichthys andruzzii . Using a new methodological approach we ascertained not only the absence o f positive chemotaxis to odour of known or unknown conspecifics, but also t he presence of a strong negative chemotaxis towards the odour of unfamiliar conspecifics and of individuals belonging to the closely related species B arbus conchonius. The biological meaning and the adaptive value of these re actions are briefly discussed.