Another missing link discovered.

>>A skeleton from the Cretaceous found in Japan reveals an early bird with a tail nub resembling the avians of today

The skeleton, named Fukuipteryx prima, was described by Fukui Prefectural University paleontologist Takuya Imai and colleagues today in Communications Biology. And while numerous birds of similar geologic age have been named in the past few decades, the details of these bones and where they were found have experts a-flutter.

In overall form, Imai and coauthors write, Fukuipteryx looks very similar to some of the earliest birds that evolved about 30 million years earlier during the Jurassic. Fingers ending in claws, for example, is a trait Fukuipteryx shares with one of the earliest known birds, Archaeopteryx. But the tail of Fukuipteryx is short and ends in a skeletal structure called a pygostyle. The bony structure is an anchor point for muscle and tail feathers, seen in modern birds and considered an important trait that birds evolved along their transition from raptor-like dinosaurs to the fliers we know today.<<

https://www.smithsonianmag.com/science-nature/newly-discovered-fossil-bird-fills-gap-between-dinosaurs-and-modern-fliers-180973551

PermeateFree said:

Another missing link discovered.

>>A skeleton from the Cretaceous found in Japan reveals an early bird with a tail nub resembling the avians of today

The skeleton, named Fukuipteryx prima, was described by Fukui Prefectural University paleontologist Takuya Imai and colleagues today in Communications Biology. And while numerous birds of similar geologic age have been named in the past few decades, the details of these bones and where they were found have experts a-flutter.

In overall form, Imai and coauthors write, Fukuipteryx looks very similar to some of the earliest birds that evolved about 30 million years earlier during the Jurassic. Fingers ending in claws, for example, is a trait Fukuipteryx shares with one of the earliest known birds, Archaeopteryx. But the tail of Fukuipteryx is short and ends in a skeletal structure called a pygostyle. The bony structure is an anchor point for muscle and tail feathers, seen in modern birds and considered an important trait that birds evolved along their transition from raptor-like dinosaurs to the fliers we know today.<<

https://www.smithsonianmag.com/science-nature/newly-discovered-fossil-bird-fills-gap-between-dinosaurs-and-modern-fliers-180973551

> the first primitive Cretaceous bird found outside China … in central Japan … “though some nonavian dinosaurs may have one of these features, only birds have all three”.

I’ve heard the word pygostyle before in connection with ancient bird or paravian fossils. I’m trying to remember where.

Nice. I have to be really careful between a bird and a paravian here. The following is my collection of paraves.

Hmm, from the following chart, archaeopteryx does not have a pygostyle (short tail) but confuciornis and sapeornis do. From the collection above, you can see the differences between the long-tailed and short-tailed paraves.