Aptian in the context of "Wulong bohaiensis"

The Nakdong Formation (Also known as the Nagdong Formation) (Korean: 낙동층; Hanja: 洛東層; RR: Nakdong-cheung) is an Early Cretaceous (Hauterivian to Aptian) geologic formation in South Korea. It has been dated from the Hauteravian to the Aptian, between 127 Ma and 118.0 ± 2.6 Ma. Plant fossils from the Nakdong Formation show 'mixed type' of the Tetori-Type and the Ryoseki-Type flora existed in this formation. Sauropod fossils have been reported from the formation, although none have yet been referred to a specific genus.

Deinonychus (/daɪˈnɒnɪkəs/ dy-NON-ih-kəs; from Ancient Greek δεινός (deinós) 'terrible' and ὄνυξ (ónux), genitive ὄνυχος (ónukhos) 'claw') is a genus of dromaeosaurid theropod dinosaur with one described species, Deinonychus antirrhopus. This species, which could grow up to 3.4 meters (11 ft) long, lived during the Early and Late Cretaceous Period, about 115–93.9 million years ago (from the mid-Aptian to Cenomanian stages). Fossils have been recovered from the U.S. states of Montana, Utah, Wyoming, and Oklahoma, in rocks of the Cloverly Formation and Antlers Formation, though teeth that may belong to Deinonychus have been found much farther east in Maryland.

Paleontologist John Ostrom's study of Deinonychus in the late 1960s revolutionized the way scientists thought about dinosaurs, leading to the "dinosaur renaissance" and igniting the debate on whether dinosaurs were warm-blooded or cold-blooded. Before this, the popular conception of dinosaurs had been one of plodding, reptilian giants. Ostrom noted the small body, sleek, horizontal posture, ratite-like spine, and especially the enlarged raptorial claws on the feet, which suggested an active, agile predator.

Mamenchisaurus (/məˌmʌntʃiˈsɔːrəs/ mə-MUN-chee-SOR-əs, or spelling pronunciation /məˌmɛntʃɪˈsɔːrəs/) is an extinct genus of sauropod dinosaurs known for their remarkably long necks, which made up nearly half the total body length. Numerous species have been assigned to the genus; however, the validity of these assignments has been questioned. Fossils have been found in the Sichuan Basin and Yunnan Province in China. Several species from the Upper Shaximiao Formation, whose geologic age is uncertain, have been described. However, evidence suggests this formation to be no earlier than the Oxfordian stage of the Late Jurassic. M. sinocanadorum dates to the Oxfordian stage (161.2 to 158.7 mya), and M. anyuensis to the Aptian stage of the Early Cretaceous (around 114.4 mya). Most species were medium-large to large sauropods, measuring roughly 15 to 26 meters (49 to 85 ft) in length—possibly up to 35 meters (115 ft), based on two undescribed vertebrae.

The Lower Greensand Group is a geological unit present across large areas of Southern England. It was deposited during the Aptian and Albian ages of the Early Cretaceous. It predominantly consists of sandstone and unconsolidated sand that were deposited in shallow marine conditions.

Oviraptorosaurs ("egg thief lizards") are a group of feathered maniraptoran dinosaurs from the Cretaceous Period of what are now Asia and North America. They are distinct for their characteristically short, beaked, parrot-like skulls, with or without bony crests atop the head. They ranged in size from Caudipteryx, which was the size of a turkey, to the 8-meter-long, 1.4-ton Gigantoraptor. The group (along with all maniraptoran dinosaurs) is close to the ancestry of birds. Some researchers such as Maryanska et al (2002) and Osmólska et al. (2004) have proposed that they may represent primitive flightless birds. The most complete oviraptorosaur specimens have been found in Asia. The North American oviraptorosaur record is sparse.

The earliest and most basal ("primitive") known oviraptorosaurs are Ningyuansaurus wangi, Protarchaeopteryx robusta and Incisivosaurus gauthieri, both from the lower Yixian Formation of China, dating to about 125 million years ago during the Aptian age of the early Cretaceous period. A tiny neck vertebra reported from the Wadhurst Clay Formation of England shares some features in common with oviraptorosaurs, and may represent an earlier occurrence of this group (at about 140 million years ago).

Pachycephalosauria (/ˌpækɪsɛfələˈsɔːriə, -ˌkɛf-/; from Greek παχυκεφαλόσαυρος for 'thick headed lizards') is a clade of ornithischian dinosaurs. Along with Ceratopsia, it makes up the clade Marginocephalia. Pachycephalosaurs lived exclusively in the Northern Hemisphere during the Cretaceous period, with all members being found in North America and Asia. They were all bipedal, herbivorous/omnivorous animals with thick skulls. Skulls can be domed, flat, or wedge-shaped depending on the species, and are all heavily ossified. The domes were often surrounded by nodes and/or spikes. Partial skeletons have been found of several pachycephalosaur species, but to date no complete skeletons have been discovered. Often isolated skull fragments are the only bones that are found.

The oldest known definitive pachycephalosaur is Zavacephale from the Early Cretaceous (Aptian-Albian) of Mongolia. Candidates for the earlier pachycephalosaurs include Ferganocephale adenticulatum from Middle Jurassic Period strata of Kyrgyzstan and Stenopelix valdensis from Early Cretaceous strata of Germany, although R.M. Sullivan has doubted that either of these species are pachycephalosaurs. Albalophosaurus from the Early Cretaceous strata of Japan might also represent a basal pachycephalosaur, as well as the undiagnostic remains of Drinker from the Late Jurassic North America. In 2017, a phylogenetic analysis conducted by Han and colleagues identified Stenopelix as a member of the Ceratopsia.