Although not well known from
fossils, the evolution of piculets is now considered rather straightforward. The disjunct occurrence of the genera, with one African species of the Southeast Asian
Sasia and one Southeast Asian species of the American
Picumnus is of comparatively recent origin. Molecular dating, calibrated with geographic events in the absence of a good fossil record, points at the Late
Miocene, c. 8
MYA, as the point where the two genera divided into their two respective lineages. At that time, there was a notable
global cooling period. The molecular distances between piculets and woodpeckers are comparatively small for subfamilies, agreeing with the hypothesis that the split between the three groups of woodpecker-like picids subfamilies occurred only during the
Miocene climatic optimum, around 15 MYA. The later radiation of South American piculets is probably due to changes in
topology and climate fluctuations during the
Pliocene and
Pleistocene. The genus
Verreauxia may be accepted because of pronounced morphological similarities, but the two
Picumnus lineages, despite having diverged long ago, are virtually alike except for head coloration. The
Antillean piculet (
Nesoctites micromegas) has proven to be a very distinct species evolutionarily between piculets and woodpeckers and thus is nowadays placed in a subfamily of its own. The arrangement of species in the genera is as follows Genus
Picumnus •
Speckled piculet,
P. innominatus •
Bar-breasted piculet,
P. aurifrons •
Orinoco piculet,
P. pumilus •
Lafresnaye's piculet,
P. lafresnayi •
Golden-spangled piculet,
P. exilis •
Black-dotted piculet,
P. nigropunctatus •
Ecuadorian piculet,
P. sclateri •
Scaled piculet,
P. squamulatus •
White-bellied piculet,
P. spilogaster •
Arrowhead piculet,
P. minutissimus •
Spotted piculet,
P. pygmaeus •
Speckle-chested piculet,
P. steindachneri •
Varzea piculet,
P. varzeae •
White-barred piculet,
P. cirratus •
Ocellated piculet,
P. dorbignyanus •
Ochre-collared piculet,
P. temminckii •
White-wedged piculet,
P. albosquamatus •
Rusty-necked piculet,
P. fuscus •
Rufous-breasted piculet,
P. rufiventris •
Ochraceous piculet,
P. limae •
Mottled piculet,
P. nebulosus •
Plain-breasted piculet,
P. castelnau •
Fine-barred piculet,
P. subtilis •
Olivaceous piculet,
P. olivaceus •
Greyish piculet,
P. granadensis •
Chestnut piculet,
P. cinnamomeus Genus
Sasia •
Rufous piculet,
S. abnormis •
White-browed piculet,
S. ochracea Genus
Verreauxia •
African piculet,
V. africana ==References==