 In a 2012 phylogenetic analysis based on mitochondrial and nuclear DNA , the plain maskray and the Ningaloo maskray ( N. ningalooensis ) were found to be the most basal members of Neotrygon . The divergence of the N. annotata lineage was estimated to have occurred ~ 54 Ma . Furthermore , the individuals sequenced in the study sorted into two genetically distinct clades , suggesting that N. annotata is a cryptic species complex . The two putative species were estimated to have diverged ~ 4 @.@ 9 Ma ; the precipitating event was likely the splitting of the ancestral population by coastline changes . 
 In a 2012 phylogenetic analysis based on mitochondrial and nuclear DNA , the plain maskray and the Ningaloo maskray ( N. ningalooensis ) <a href='uninflect' title='1'><mark>were</mark></a> found to be the most basal members of Neotrygon . The divergence of the N. annotata lineage was estimated to <a href='been_done' title='2'><mark>have</mark></a> occurred ~ 54 Ma . Furthermore , the individuals sequenced in the study sorted into two genetically distinct clades , suggesting that N. annotata is a cryptic species complex . The two putative species <a href='uninflect' title='3'><mark>were</mark></a> estimated to <a href='been_done' title='4'><mark>have</mark></a> diverged ~ 4 @.@ 9 Ma ; the precipitating event was likely the splitting of the ancestral population by coastline changes . 
In a 2012 phylogenetic analysis based on mitochondrial and nuclear DNA , the plain maskray and the Ningaloo maskray ( N. ningalooensis ) was found to b da most basal members of Neotrygon . The divergence of the N. annotata lineage was estimated to done occurred ~ 54 Ma . Furthermore , the individuals sequenced in tdastudy sorted into two genetically distinct clades , suggesting that N. annotata is a cryptic species complex . The 2 putative species was estimated to done diverged ~ 4 @.@ 9 Ma ; the precipitating event was likely thdaplitting of the ancestral population by coastline changes .