Euparaves

In order to talk about the origin of primitive birds it is necessary to introduce a new clade name, Euparaves.
Euparaves (node-based) definition:
"The most recent common ancestor of Epidendrosaurus ninchengensis (Scansoriopterygidae) and Passer domesticus (the house sparrow), and all descendants thereof".

Here is the stem-based definition of Euparaves:
"The most inclusive clade containing Passer domesticus (Linnaeus 1758) but not Pterorhynchus wellnhoferi."

Here is the apomorphy-based definition of Euparaves:
possessed remiges and rectrices, that is, enlarged, stiff-shafted, closed-vaned (= barbules bearing hooked distal pennulae), pennaceous feathers arising from the distal forelimbs and tail
AND
possessed feathered wings used in flapping flight



Alvarezsaurids and oviraptors are taxa within Euparaves. They are secondarily flightless, primitive birds that descended from flying basal Euparaves.

Here is a sample of flying, basal Euparavians:
Scansoriopterygids (Temporal range: Late Jurassic, 165–156 Ma)
Anchiornis (Temporal range: Late Jurassic, 161–160.5 Ma)
Aurornis (Temporal range: Late Jurassic, 160 Ma)
Xiaotingia (Temporal range: Late Jurassic, 160 Ma)
Pedopenna (Temporal range: Middle or Late Jurassic, 164 Ma)

These require further analysis:
Eosinopteryx? (Temporal range: Late Jurassic, 160 Ma)
Zhongornis? (Temporal range: Early Cretaceous, 122 Ma)
Zhenyuanlong?
Archaeopteryx?
Microraptor?
Jeholornis?
Ornithomimosaurs?
Therizinosaurids?
Velociraptor?
Jixiangornis?


Note.
Oviraptors, Alvarezsaurids and Eudromaeosaurids are secondarily flightless, primitive birds within Euparaves.