Biosis: Biological Systems

Phyllotheca douroensis sp. nov., a new equisetalean fossil-species from the Douro Carboniferous Basin (Upper Pennsylvanian; NW Portugal): palaeobiogeographical, systematic and evolutionary implications

Catarina Barbosa — 2022-03-23

The first occurrence of the fossil-genus Phyllotheca (Equisetales) from the Carboniferous of Portugal is documented and its palaeobiogeographical, systematic and evolutionary significance is assessed. In this paper, we described this new equisetalean fossil as new species, Phyllotheca douroensis sp. nov., found in the Douro Carboniferous Basin (lower Stephanian C/lower Gzhelian, Upper Pennsylvanian), in northwestern Portugal. P. douroensis sp. nov. represents a convergent form of Phyllothecaceae sensu lato (comprises the Angaran Tchernoviaceae and the Gondwanan Gondwanostachyaceae) with closer affinities to Euramerican floral province.

A Preliminary Review of Dinosaur Track Assemblages from the Tuchengzi Formation in North China

Lida Xing — 2022-03-23

In northern China, mainly within Western Liaoning, Northern Hebei and Beijing, vertebrate skeletons from the Tuchengzi Formation (Upper Jurassic to Lower Cretaceous) are scarce. However, a large number of new dinosaur track discoveries have made in past 10 years. So far, a total of 19 dinosaur track sites have been found in the Tuchengzi Formation, collectively containing 2,637 individual tracks and representing at least 2,091 trackmakers. This track record has become an important sample for understanding the Tuchengzi dinosaur fauna. The abundant Tuchengzi track record includes six non-avian theropod ichnogenera (Asianopodus, Eubrontes, Grallator, Menglongipus, Therangospodus, and Velociraptorichnus), three bird ichnogenera (Aquatilavipes, Pullornipes, and Koreanaornis), two sauropod ichnogenera (Brontopodus and cf. Parabrontopodus isp.), and a possible ornithopod ichnogenus (cf. Dinehichnu). This assemblage is saurischian-dominated, which is consistent with most Jurassic and Cretaceous track sites in China. The presence of deinonychosaurian tracks is consistent with the rich skeletal record from the Yanliao Biota or Jehol Biota, and the bird tracks are consistent with the record of shorebirds in Jehol Biota. The existence of ornithopod tracks is doubtful and needs further discoveries to be confirmed.

Dinosaur Track from the Jurassic Xiahuayuan Formation of Northern China

Lida Xing — 2022-04-01

An isolated but moderately well-preserved theropod track from the coal-bearing strata of the Zhangjiakou City region of Hebei Province was reported to have originated from the Xiahuayuan Formation, which is considered Middle Jurassic in age. Although the track has a wide divarication angle and length-width ratio reminiscent of Cretaceous tracks like Magnoavipes, it would be speculative to apply this Identification based on a single track. Therefore, it is considered most likely to be a preservational variant of Kayentapus, in which the heel trace is lacking. Kayentapus is widely known from the Lower Jurassic of China. This is the first report of a track or any vertebrate fossil from the Middle Jurassic of this region of Hebei Province, China.

Dinosaur Tracks from the Lower Jurassic Lufeng Formation of Northern Central Yunnan, China

Lida Xing — 2022-04-01

An increasing number of theropod-dominated tracksites have been reported from the Jurassic and Cretaceous of China. These include a significant number from the Lower Jurassic of the Lufeng Basin, famous for its Lufengosaurus fauna and known for a typical Lower Jurassic globally-distributed tetrapod footprint biochron. Here we report another localized theropod track occurrence regular of various scattered tracksites from the Lufeng Formation. The tracks are medium-sized tridactyl tracks from the basal member of the Zhangjia'ao Member, Lufeng Formation which shows an unusually wide divarication between the traces of digits III and IV, which suggest several possible interpretations.