Color patterns of the hermit crab Calcinus tibicen (Herbst, 1791) fail to indicate high genetic variation within COI gene

Abstract Apart from traditional characters, other data have been used for taxonomy, like color patterns. Based on the different colors (green and orange) observed for some Calcinus tibicen (Herbst, 1761) specimens, we evaluated the genetic distance for cytochrome oxidase subunit I mitochondrial gene of individuals collected in Pernambuco (northern Brazil) and in São Paulo (southeast Brazil). We found low genetic variation (0.2-1.1%), and no evidence of isolation on our molecular tree based on genetic distance. We suggest high levels of gene flow between specimens with different color patterns, which are polymorphisms and might be related to the kind of nutrition as well different ecological and evolutionary predation characteristics.