MP analyses based on Vaz-2006 matrices also most often showed Dasyatis sp and D.americana specimens as composing a single clade (Figure 4; Table 2). In fact, the phylogenetic
signal of Vaz-2006 matrices was even stronger than that of the present-study matrices.
For instance, analysis of the Vaz-2006 OPK 11 data matrix grouped D. americana and Dasyatis sp
as a single clade, whereas that of the present-study OPK 11 matrix failed to do so (see Table 2).
The NJ tree based on Vaz-2006 matrices also placed Dasyatis sp and D. americana
in a single clade (Figure 5). The genetic distance (uncorrected P) between Dasyatis
sp and any of the other four D. americana individuals ranged from 0.055 to 0.066. In
contrast, the genetic distances ranged from 0.396 to 0.445 between D. americana and D.
guttata, from 0.319 to 0.341 between D. americana and D. marianae, and from 0.357 to
0.385 between D. guttata and D. marianae.