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Our understanding of the evolutionary sequence of tetrapod characters is hindered by a limited fossil record of primitive finned tetrapods. This study reports a new stem-tetrapod from ~409 million years ago, which displays morphological features shared by tetrapods and lungfishes, and extends the earliest record of tetrapods by ~10 million years.

This study presents an exceptionally well-preserved fossil fish from the Silurian period (more than 418 million years ago) from southern China. The new form shows a mix of derived and primitive features. It is the earliest known well-preserved bony fish, and is a basal member of the lobe-finned fishes (which includes, today, the lungfishes, coelacanth and all land vertebrates), meaning that the split between ray-finned and lobe-finned bony fishes must have happened at least 419 million years ago, suggesting a deep history for jawed vertebrates.

A primitive fossil species of lobe-finned fish combines many histological features found in both ray-finned bony fishes and lobe-finned bony fishes.

Direct evidence for the presence of jawed vertebrates in the early Silurian (around 439 million years ago) is provided by isolated tooth whorls of the gnathostome Qianodus duplicis from Guizhou province, China.

Fanjingshania renovata possesses dermal shoulder girdle plates and fin spines similar to those of a subset of stem chondrichthyans, but also has osteichthyan-like resorptive shedding of scale odontodes and an absence of odontogenic tissues in its spines.

The coelacanth body plan can be traced to the late Middle Devonian, but the group's early history is unclear due to a limited fossil record. This study presents the earliest known coelacanth skull (Euporosteus yunnanensissp. nov.), extending the chronological range of anatomically modern coelacanths by 17 million years.

Although the origin of jaws is one of the key episodes in the evolution of vertebrates, the jaw bones of modern bony fishes and limbed vertebrates differ so much from those in any other groups that the individual evolutionary steps in the transition are still unknown; here Entelognathus is described, an early placoderm fish with full body armour, but with marginal jaw bones similar to those of modern bony fishes and limbed vertebrates.