In the geologic timescale, the Callovian is an age and stage in the Middle Jurassic, lasting between 165.3 ± 1.1 Ma and 161.5 ± 1.0 Ma. It is the last stage of the Middle Jurassic, following the Bathonian and preceding the Oxfordian.
Atlasaurus is a genus of sauropod dinosaurs from Middle Jurassic beds in North Africa.
The San Rafael Group is a geologic group or collection of related rock formations that is spread across the U.S. states of New Mexico, Arizona, Utah and Colorado. As part of the Colorado Plateau, this group of formations was laid down in the Middle Jurassic during the Bajocian, Bathonian and Callovian Stages.
The Carmel Formation is a geologic formation in the San Rafael Group that is spread across the U.S. states of Wyoming, Utah, Colorado, north east Arizona and New Mexico. Part of the Colorado Plateau, this formation was laid down in the Middle Jurassic during the late Bajocian, through the Bathonian and into the early Callovian stages.
Bittacidae is a family of scorpionflies commonly called hangingflies or hanging scorpionflies.
Metriorhynchus is an extinct genus of marine crocodyliform that lived in the oceans during the Late Jurassic. The type species, M. brevirostris was named in 1829 as a species of Steneosaurus before being named as a separate genus by the German palaeontologist Christian von Meyer in 1832. The name Metriorhynchus means "Moderate snout", and is derived from the Greek Metrio- ("moderate") and -rhynchos ("snout").
Sphenosuchia is a suborder of basal crocodylomorphs that first appeared in the Triassic and occurred into the Middle Jurassic. Most were small, gracile animals with an erect limb posture. They are now thought to be ancestral to crocodyliforms, a group which includes all living crocodilians.
Osmylidae are a small family of winged insects of the net-winged insect order Neuroptera. The osmylids, also called lance lacewings, stream lacewings or giant lacewings, are found all over the world except North and Central America. There are around 225 extant species.
The Shaximiao Formation is a Middle to Late Jurassic aged geological formation in Sichuan, China, most notable for the wealth of dinosaurs fossils that have been excavated from its strata. The Shaximiao Formation is exposed in and around the small township of Dashanpu, situated seven kilometres north-east from Sichuan's third largest city, Zigong, in the Da'an District.
The Kota Formation is a geological formation in India. The age of the Kota Formation is uncertain; it is commonly considered to date to the Early Jurassic, but some studies have suggested it may extend into the Middle Jurassic or even later. It conformably overlies the Lower Jurassic Upper Dharmaram Formation and is unconformably overlain by the Lower Cretaceous Gangapur Formation. It is split into a Lower Member and Upper Member. The Lower Member is approximately 100 m thick while the Upper Member is 490 m thick. Both subunits primarily consist of mudstone and sandstone, but near the base of the upper unit there is a 20-30 metre thick succession of limestone deposited in a freshwater setting.
The Taynton Limestone is a geological formation in Oxfordshire in the United Kingdom. It dates to the Middle Jurassic, mid-Bathonian stage. It predominantly consists of ooidal grainstone. The term "Stonesfield Slate" refers to slaty limestone horizons within the formation that during the 18th and 19th centuries were extensively quarried for use in roof tiling within the vicinity of Stonesfield, Oxfordshire. Previously these were thought to belong to the Sharp's Hill Formation, but boreholes and shaft sections suggest that at least three horizons within the Taynton Limestone were quarried for the slate. These horizons are well known for producing a diverse set of fossils including those of plants, insects as well as vertebrates, including some of the earliest known mammals, pterosaurs as well as those of first dinosaur ever described, Megalosaurus.
The Forest Marble is a geological formation in England. Part of the Great Oolite Group, it dates to the late Bathonian stage of the Middle Jurassic.
The Isalo III Formation is a geological formation in Madagascar, off the eastern coast of Africa. It dates back to the Middle Jurassic. The use of the term "Isalo III" is somewhat controversial as the two prior units Isalo I and II are Triassic cross-bedded sandstone units that form a continuous depositional sequence, while the "Isalo III" sandstones are not part of the same depositional sequence, and were deposited considerably later. and are perhaps better treated as part of several separate formations. It is traditionally divided into two subunits the lower, Bajocian aged Isalo IIIa unit also known as the Beronono Formation and the upper, Bathonian aged Isalo IIIb unit also known as the Sakaraha Formation or Sakahara Formation. The Sakaraha Formation consists of sandstones, marls and carbonates and represents a coastal plain environment, and is laterally equivalent to the predominantly carbonate Bemaraha Formation, which represents a coastal barrier lagoon complex. The formation is found in the northwest and in the southeast of the country and has provided a variety of fossils.
The Balabansai Formation is a geological formation in Kazakhstan, Kyrgyzstan and Uzbekistan whose strata date back to the Bathonian and Callovian stages of the Middle Jurassic. Dinosaur remains are among the fossils that have been recovered from the formation. The lithology primarily consists of variegated sandstones, siltstones, claystones, and rare gravels and marls. Many taxa have been found in the formation, including amphibians and mammals
Brachyphyllum is a form genus of fossil coniferous plant foliage. Plants of the genus have been variously assigned to several different conifer groups including Araucariaceae and Cheirolepidiaceae. They are known from around the globe from the Late Carboniferous to the Late Cretaceous periods. B. sattlerae was named after the fictional palaebotanist Ellie Sattler from the Jurassic Park franchise.
The Duntulm Formation is a sedimentary geologic formation deposited in the Inner Hebrides, Scotland. The formation was previously known as the 'Lower Ostrea Beds', and dates to the Bathonian stage of the Middle Jurassic. The formation is noted for its highly fossiliferous oyster beds, which compose of the species Praeexogyra hebridica. The sedimentary sequence also forms part of the Great Estuarine Group.
The Kilmaluag Formation is a Middle Jurassic geologic formation in Scotland. It was formerly known as the Ostracod Limestone for preserving an abundance of fossil freshwater/low salinity ostracods. Gastropods, bivalves, trace fossil burrows, and vertebrate fossil remains have also been recorded from the formation. Vertebrate fossils include fish, crocodylomorphs, mammals, small reptiles, amphibians, theropod and sauropod dinosaurs and pterosaurs.
The Jaisalmer Formation is a Middle to Late Jurassic-aged geologic formation located in India near the city of Jaisalmer that consists mainly of marine deposits. The formation was first identified and defined by geologist Richard Dixon Oldham in 1886.
Strophodus is an extinct genus of durophagous hybodont known from the Triassic to Cretaceous. It was formerly confused with Asteracanthus.
Planohybodus is an extinct genus of hybodont, known from the Middle Jurassic-Early Cretaceous (Bathonian-Barremian) of Europe and the Indian subcontinent. Fossils have been found in marine as well as freshwater environments. The genus contains 3 confirmed species, two of which were originally assigned to the genus Hybodus. Possible records have been reported from the Late Jurassic of Mexico, the Early Cretaceous of Brazil and the Late Cretaceous (Santonian) of North America, but these are unconfirmed. Planohybodus peterboroughensis is suggested to have reached lengths of 2–3 metres (6.6–9.8 ft). A specimen of the ammonite genus Orthaspidoceras from the Late Jurassic of France has been found with an embedded tooth of Planohybodus, suggesting that while the teeth of Planohybodus were adapted to tearing soft bodied prey, it would attack hard-shelled prey at least on occasion.
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