Diagnosis of phenotypes of Symphysodon using the methodology and criteria of Crandall et al. [61]. Lower diagonal—tests of hypotheses of genetic (left column) and ecological (right column) exchangeability during recent (upper row) and historical (lower row) times: + = null hypothesis rejected; − = null hypothesis not rejected. Upper diagonal—Inference of ESU categories: Case  1 = long separated species; Case  2 = distinct species; Case  3 = distinct populations (recent admixture and loss of genetic distinctness); Cases  7 and  8 = single population.