Archaeopteryx sp. (private, undescribed) is a small Solnhofen (Late Jurassic) bird basal to the Scansoriopterygidae. Note the relatively small, wide skull and large premaxillary teeth.

Archaeopteryx bavarica (BSP 1999 I 50, Wellnhofer 1999) nests between the #12 specimen, above, and the rest of the Scansoriopterygidae. Note the third finger is still short, but more robust. Later taxa elongate this finger.

Jeholornis prima (LPM 0193, Wellnhofer 199, 80cm long) is a large archaeopteryx-like flightless bird at the base of the Scansoriopterygidae. The third finger is longer than the second here.

Archaeovolans repatriatus (IVPP V12444, Czerkas and Xu 2002) This Early Cretaceous bird had a controversial beginning as Archaeoraptor liaoningensis). Zhou and Zhang (2002) considered the specimen another Yanornis, but it does not nest with Yanornis in the large reptile tree, but with the flightless scansoriopterygid, Mei. So it would have had long legs, a long stiff tail and probably a long pedal digit 3. Manual digit 3 was longer and more robust than the other digits.

Mei long (IVPP V12733, Xu and Norell 2004, Early Cretaceous) is famous for its 3D preservation in a curled up sleeping posture. Originally considered a young juvenile, bird-like troodontid, Mei long nests in the large reptile tree between the xx specimen of Archaeopteryx and Scansoriopteryx amid the scansoriopterygid basal birds. A second specimen, DNHM D2154 (Gao et al. 2012), was also preserved in a sleeping posture. Mei is derived from a sister to the Munich specimen of Archaeopteryx and was basal to other scansoriopterygids.

Czerkas SA and Yuan C 2002. An arboreal maniraptoran from northeast China. Pp. 63-95 in Czerkas, S.J. (Ed.), Feathered Dinosaurs and the Origin of Flight. The Dinosaur Museum Journal 1. The Dinosaur Museum, Blanding, U.S.A.

Czerkas SA and Ji Q 2002. A preliminary report on an omnivorous volant bird from northeast China. In: Czerkas, SJ (editor): Feathered Dinosaurs and the origin of flight. The Dinosaur Museum Journal 1:127-135.

Xu X, Zheng X-T, Sullivan C, Wang X-L, Xing l, Wang Y, Zhang X-M, O’Connor JK, Zhang F-C and Pan Y-H 2015. A bizarre Jurassic maniraptoran theropod with preserved evidence of membranous wings. Nature (advance online publication)
doi:10.1038/nature14423

Zhang F, Zhou Z-H, Xu X, Wang X and Sullivan C 2008. A bizarre Jurassic maniraptoran from China with elongate ribbon-like feathers. Nature 455 doi:10.1038:1105-1108.

Xu X and Norell MA 2004. A new troodontid dinosaur from China with avian-like sleeping posture. Nature 431:838-841.

Gao C, Morschhauser EM, Varricchio DJ, Liu J, Zhao B 2012. Farke AA ed. "A Second Soundly Sleeping Dragon: New Anatomical Details of the Chinese Troodontid Mei long with Implications for Phylogeny and Taphonomy". PLoS ONE 7 (9): e45203. doi:10.1371/journal.pone.0045203. PMC 3459897. PMID 23028847.

wiki/Jeholornis
wiki/Archaeovolans
wiki/Mei
wiki/Omnivoropteryx