Skeletal variability of the coral Favia gravida (Verrill, 1868) from Brazil

Abstract

The skeletal variability of the coral Favia gravida, a species endemic to Brazil, was quantitatively described including populations from three locations: Tamandaré (state of Pernambuco), Abrolhos (state of Bahia), and Santa Cruz (state of Espírito Santo). Ten colonies were collected from each population and fourteen morphological characters were measured from ten corallites per colony. The results of univariate (among 14 skeletal characters, 7 showed p < 0.05) analysis provide evidence to suggest that F. gravida has considerable morphological plasticity, which may explain its ability to adapt to different ecological conditions. The species also displays polymorphism within and between colonies of each population. Intercolony variation within populations was relevant for most of the variables measured. Canonical discriminant analysis (r = 0.8648) showed that the population farthest offshore (Abrolhos) was distinct from the other two (Tamandaré and Santa Cruz), which have been affected by terrigenous sediments carried from the coast. Specimens from Santa Cruz displayed the highest degree of meandrinization.