Abstract:
Red-fronted Tinkerbird Pogoniulus pusillus (Dumont, 1816) presently
comprises three recognised subspecies, of which two are found in East Africa and
one occurs disjunctly in southern Africa. Based on their respective distributions
and phenotypic differences, a taxonomic reassessment of the species is warranted.
We performed a phylogenetic reconstruction using the mitochondrial genes
ATPase 6/8 based on 33 samples from across the distribution of Red-fronted
Tinkerbird and four outgroup samples, and then determined correspondence
between genetic distances and differences in song and morphology among clades
using the Tobias et al. criteria. Our phylogenetic analyses revealed 4.4% sequence
divergence in mtDNA between northern and southern populations, with plumage,
morphometric and song differences of a similar magnitude to those between
P. pusillus and Yellow-fronted Tinkerbird P. chrysoconus, and above species-level
thresholds according to the Tobias et al. criteria. Furthermore, the molecular
phylogeny supports recognition of a synonymised taxon (P. p. eupterus) as a
distinct, but phenotypically cryptic, subspecies in East Africa, with c.1.5% sequence
divergence from P. p. affinis and P. p. uropygialis, which in turn differ less (1%)
from each other. We propose that northern and southern Red-fronted Tinkerbirds
are treated as separate species, and that the subspecies eupterus is resurrected. Our findings suggest that P. chrysoconus as presently constituted may also merit
taxonomic revision.
