Here we have the two species of finch-like passeriform birds that had been described at the beginning of this year, Eofringillirostrum boudreauxi and Eofringillirostrum parvulum, both from the Eocene, the first from North America, the second, smaller species from Europe.
Eofringillirostrum boudreauxi Mayr, Ksepka & Grande
This is the larger of the two known species, reaching about 10 cm in length, it also is the older one, having lived in the Early Eocene about 52 Million years ago in what today is Wyoming, USA.
This is what I call a pre-sketch, or a working sketch, it’s just the very first step in reconstructing a fossil bird, in which this particular species is drawn in a simple side-view, usually smaller than life-size.
Eofringillirostrum parvulum Mayr, Ksepka & Grande
This bird may have reached a length of only about 9 cm, it lived in the Middle Eocene of what today is the State of Hesse in Germany.
I sketched it together with a reconstructed infructescence of Volkeria messelensis Smith, Collinson et al., a plant from the family Cyperaceae that was growing around the Messel lake, and whose seeds may indeed have been eaten by this presumably seed-eating bird.
This bird was described in 2010, it was then thought to be somehow related to the Charadriiformes respectively to the Charadriiformes “orbit”, later it was assumed to belong in some kind of relationship with other likewise “well-known” birds like Eocuculus cherpinae (Chandler), or Pumiliornis tessellatus Mayr.
The reconstruction shows a tiny bird, some 12 cm long, with a sharp-pointed beak and a quite long neck, such a bird would have needed long tail feathers to stabilize its body – so I just gave it a long tail, cause the feathers are not preserved in the Fur Formation birds.
So here is how all begins, some cut-out bone drawings put together, lines made with a pencil etc..:
The final result is a quite life-like bird, maybe I got enough time to make a real painting, with colors and so on ….:
 Sara Bertelli; Bent K. Lindow; Gareth J. Dyke; Luis M. Chiappe: A well-preserved ‘charadriform-like’ fossil bird from the Early Eocene Fur Formation of Denmark. Paleontology 53(3): 507-531. 2010  Gerald Mayr: On the osteology and phylogenetic affinitis of Morsoravis sedilis (Aves) from the early Eocene Fur Formation of Denmark. Bulletin of the Geological Society of Denmark 59: 23-35. 2011
This genus currently contains two species, which mainly differ by their size, Songzia acutunguis Wang et al. and the slightly smaller Songzia heidangkouensis Hou.
These two species have much in common with the recent species of the rail family, yet may not be related to them, but may be closer to the extinct Messel ‘Rails’, the Messelornithidae, which themselves may or may not be members of the Gruiformes.
The two Songzia ‘Rails’ are small, sparrow-sized birds, in life they probably inhabited the margins of lakes and other swampy areas.
The picture is just a sketch.
Feather impressions are not known to my knowledge, however, I thought it would be a good idea to give the bird somewhat elongated tail feathers, since the feather impressions in some messelornithid fossils show that these birds had very long tail feathers.
 Min Wang; Gerald Mayr; Jiangyong Zhang; Zhonghe Zhou: Two new skeletons of the enigmatic, rail-like avian taxon Songzia Hou, 1990 (Songziidae) from the early Eocene of China. Alcheringa: An Australian Journal of Palaeontology 36: 487-499. 2012