Phylogeny and genetic differentiation
Both Microlophus and Phyllodactylus phylogenetic trees are
similar in that (1) they support the monophyly of the two study species,
(2) the individuals from Gardner, Champion and Floreana form three
separate clades, respectively, and (3) Champion and Floreana clades are
closely related (Fig. 2). The only exception to (2) and (3) is the only
individual of M. grayii (AY625170) from Black Beach (Floreana),
which is sister to the Champion clade. M. grayii is moderately
supported (BS [bootstrap support] =62) as sister to a clade
containing a paraphyletic M. albemarlensis (Isabela and
Fernandina) and M. pacificus (Pinta). P. baurii is weakly
(BS=40) supported as sister to a clade containing P. galapagensis(Santa Cruz), a paraphyletic P. maresi (Santiago), P.
simpsoni (Isabela), and P. duncanensis (Pinzón).
Interspecific genetic distances (ND2) among species of the
‘Microlophus Western Radiation’ (Benavides et al., 2009) vary
between 0.038–0.149 (average=0.094, SD=0.031), whereas intraspecific
distances for M. grayii are 0.036 on average. Within M.
grayii , the largest distances are between samples from Gardner and
those from Floreana and Champion combined (0.068 on average). Similarly,
interspecific genetic distances (ND4) among species of the ‘P.
galapagensis Radiation’ (Torres-Carvajal et al., 2014) vary between
0.049–0.155 (average=0.108, SD=0.032), whereas intraspecific distances
for P. baurii are 0.014 on average. Within P. baurii , the
largest distances are between samples from Gardner and those from
Floreana and Champion combined (0.026 on average).