Variación morfometrica de Chiton stokesii (Polyplacophora: Chitonidae) en un gradiente intermareal del Parque Nacional Natural Isla Gorgona

Abstract

Chiton stokesii is a species of polyplacophora of the marine rocky ecosystem in Gorgona Island. Objective : To examine the morphological variation of C. stokesii according to the location in an intertidal gradient. Methodology : A plot of 4 x 29 m was constructed where a height pro le was constructed. Within the pro le of heights 13 reference points were marked, which were used to calculate the intertidal height to which each individual was. In addition, four measurements were made on each specimen: Length and width of the fourth dorsal plate, and length and width of the individual. Descriptive analyzes, linear regressions and analysis of ANOVA and ANCOVA were performed to verify the e ect of intertidal height on the morphology of this species. Results : A total of 101 individuals were measured from seven to 412 centimeters above the zero tide level, of which 29 individuals were found in the lower zone, 62 in the middle zone and 10 in the upper intertidal zone; The statistical tests do not reject the null hypothesis (p>0.05), the long-regression analyzes show a greater adjustment in the individual’s measurements. Conclusion : There is no association between morphometry and intertidal height. The evidence presented is not conclusive and opens the way to new questions in future population studies of this species in protected areas.